The car A will hit the car B during the reaction time of 0.5 seconds, and the distance the car will travel during the reaction time is 13.5 meters.
Reaction time is the time taken by the driver between seeing the scenario in front of his/her eye and the instant of applying the break. It is derived by the PIEV theory. The PIEV theory includes the time durations which drivers see, recognize, analyze and react to apply the brake for avoiding objects on the roads. The PIEV time on highway design engineering is taken as 2.5 seconds.
Given the speed of the car A is 27 m/s
Reaction time = 0.5 sec
Distance travelled, d = 27 × 0.5 = 13.5 meters
As the distance travelled by the car A is more than the distance between car A and car B, so the car will surely hit the car B.
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a pharmacy technician measures the mass of a pill. the mass of one pill is . what is the mass in kilograms of pills? write your answer as a decimal.
The mass of one pill measured was 461 mg and for the same pill, the mass in kilograms of 100 pills will result to 46l*100/100000 => 0.046l kg. As there are 1 ms = 10^-5 kg.
What is a pharmacy technician? A pharmacy technician is a person in pharma who decides the composition of the chemicals in medicine and the size of medicine from manufacturing.
The mass of one pill is given as 461 mg and the number of pills required is 100So the total mass will be, mass of 1 pill*100 = 461 mg × 100 = 46100mg
one kilogram = 1000 grams, so the mass in kilograms will be, The same mass in kg will be 46100mg / 1000 grams
which results in 0.046l kg.
This simply shows, the mass of 1 pill was 461 mg the mass in kilograms of 100 pills will be 0.046l kg for measurements of the mass in kg of a pill.
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HELPP PLEASE THANK YOUUU
The label B in the diagram represents wavelength (last option)
How do I know what label B represents?We'll determine what label B represents by defining the options given. This is shown below:
Crest: This is the maximum value of the upward displacement of a progressive wave.
Amplitude: This is the maximum displacement of a wave.
Trough: This is the minimum value of the downward displacement of a progressive wave.
Wavelength: This is the distance between two successive crest or trough of a wave
Now, we can see clearly that label B exist bewteen two crest.
Thus, from the definitions given above, we can conclude that lebel B represents wavelength (last option)
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what are the approximate dimensions of the smallest object on earth that astronauts can resolve by eye when they are orbiting
Approximate size s 700 is 29.4 m
Find Approximate size?The diffraction limit, which may be calculated using the formula = 1.22 / D, establishes the limit of the human eye's solution.
The circular aperture's mediator, D, and the wavelength are where you lick them.
The eye responds to wavelengths between 400 nm and 700 nm in our situation, where the dilated pupil has a diameter of about 8 mm = 8 10-3 m.
the formula is amended by including these values
λ = 400 nm θ = 1.22 400 10⁻⁹ / 8 10⁻³ = 6 10⁻⁵ rad
λ = 700 nm θ = 1.22 700 10⁻⁹ / 8 10⁻³-3 = 1.07 10⁻⁴ rad
The definition of radians is now: radians = s / R.
where the radius is R and s is the supported arc. For each scenario, let's identify the sarcos.
λ = 400 nm s 400 = θ R
S 400 = 6 10⁻⁵ 275
λ = 700 nm s_ 700 = 1.07 10⁻⁴ 275 10³
s 700 = 29.4 m.
The complete question is,
What is the smallest item on Earth that astronauts can see by eye when circling 275 kilometers above the planet and what is its approximate size?
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the student explains how conduction is the charging by contact so the uncharged object takes
The student explains that conduction is the process of charging an object by touch. When two oppositely charged conductors make contact, this charge is divided between two conductors and is transferred to the uncharged conductor, which charges the conductor.
What is the conduction phenomenon explained?Conduction is one of the three main ways that heat energy is transferred.
When neighbouring atoms or molecules collide, heat energy is delivered by conduction.Conduction occurs more readily in both liquids and solids with smaller particle spacing than in gases with larger particle spacing.A rate of energy transfer by conduction is accelerated when there is a large temperature difference between the materials in contact.One class of solids that effectively transport heat is metals.Unsurprisingly, many pots and pans have insulated handles. A gaseous mixture of water and air is a poor conductor of thermal energy. They have the name "insulators."Consequently, When two oppositely charged conductors make contact, this charge is divided between two conductors and is transferred to the uncharged conductor, which charges the conductor.
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a 0.15 kg ball is thrown with a speed of 20.0 m/s. it is hit straight back at the pitcher with a final speed of 22.0 m/s. (a) what is the impulse delivered by the bat to the ball? (b) find the average force exerted by the bat on the ball if the two are in contact for 2.0 x 10-3 s
The average force exerted by the bat on the ball is 3200N and the impulse delivered by the bat on the ball is 6.30kgm/s
(a) The impulse delivered by the bat to the ball can be calculated using the equation Impulse = Change in Momentum.
Therefore, the impulse is equal to the difference between the final momentum and the initial momentum of the ball.
mΔv=0.15×42=6.3kgm/s
(b) The average force exerted by the bat on the ball can be calculated using the equation Force = Impulse/Time. Therefore, the average force is equal to the impulse divided by the time that the two are in contact. The time is 2 × [tex]10^{-3}[/tex]s. Therefore, the average force is equal to 150 N.
6.30/2×[tex]10^{-3}[/tex]= 3200N
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which scenario describes a closed system in which momentum will be fully conserved? physics is beautiful
A bullet fired from a gun is the scenario which describes conservation of momentum.
A closed system is one which is not affected by the any external force or activity. When a bullet is fired from a gun it generates a recoil velocity in the gun. This is due to the conservation of momentum. Initially the momentum of the system (gun + bullet) is zero. When a bullet is fired because of having less mass as compared to the gun, it escape out with more velocity. To conserve the momentum of the system the gun also generates velocity in the backward direction. Due to the heavy mass of the gun as compared to the bullet, this velocity is very less, which is called recoil velocity.
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when you define a system to determine the temperature rise created in a lake when a portion of its water is used to cool a nearby electrical power plant, should we account for all the forms of water entering and leaving the volume selected?
All forms of water entering and leaving the volume selected should be accounted for in order to accurately determine the temperature rise in the lake caused by the power plant.
When determining the temperature rise of a lake caused by a nearby power plant, it is important to consider all forms of water entering and leaving the selected volume.
This includes not only the water being withdrawn and returned by the power plant, but also any other sources of water entering or leaving the lake, such as precipitation, evaporation, and surface or ground water flow.
By accounting for all of these inputs and outputs, a more accurate understanding of the overall heat balance of the lake can be obtained and the impact of the power plant on the lake's temperature can be better understood.
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The tendency for a material to oppose the flow of electrons is called_____.
When a material tends to obstruct the flow of electrons, electrical energy is converted into heat energy and light. All materials have a characteristic called electrical resistance. Ohms, or, are used to measure resistance.
The flow of electrons is in the opposite direction from the flow of current. Resistance is a conductor quality that prevents current from flowing. Electrons and ions collide as they pass across a conducting wire. The current is decreased as a result of these collisions, which convert some kinetic energy into thermal energy. The ohm is the SI unit of resistance. Regarding the movement of electrons, they naturally gravitate towards the +ve side due to their -ve charge, which is the opposite of the traditional direction of current flow (from +ve to -ve).
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the mass of fuel in a jet must be calculated before each flight to ensure that the jet is not too heavy to fly. a 747 is fueled with 173,231 l of jet fuel. if the density of the fuel is 0.768 g / cm3 , what is the mass of the fuel in kilograms (kg)?
The mass of the fuel is 133 kilograms. The result is obtained by using the formula for the density.
What is the density of a substance?The density is the mass of a substance per unit of volume. It can be expressed as
ρ = m/V
Where
ρ = densitym = massV = volumeA jet 747 is fueled with jet fuel.
V = 173.231 L ρ = 0.768 g/cm³Find the mass of the fuel!
We convert the units of volume and density.
V = 173.231 L
V = 173.231 dm³
V = 173.231 × 1/1000 m³
V = 0.173231 m³
ρ = 0.768 g/cm³
ρ = 0.768 × 1000 kg/m³
ρ = 768 kg/m³
Using the formula for a density, we will get the mass.
ρ = m/V
768 = m/0.173231
m = 0.173231 × 768
m ≈ 133 kg
Hence, the jet fuel has a mass of 133 kilograms.
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PLEASE DO ASAP WILL GIVE BRAINLIEST!!!
An initially neutral and non-polarized conducting rod is moving to the right at a constant speed v through a large region that has a uniform magnetic field, as shown above. Which of the following statements correctly describes the motion of the particles within the rod and the resulting charge separation in the rod caused by this motion?
(A) Positively charged particles within the rod moved downward, causing the bottom of the rod to have a positive charge and the top to have a negative charge.
(B) Negatively charged particles moved upward, causing the bottom of the rod to have a positive charge and the top to have a negative charge.
(C) Positively charged particles moved upward, causing the top of the rod to have a positive charge and the bottom of the rod to have a negative charge.
(D) Negatively charged particles moved downward, causing the top of the rod to have a positive charge and the bottom of the rod to have a negative charge.
Answer:
C
Explanation:
(C) Positively charged particles moved upward, causing the top of the rod to have a positive charge and the bottom of the rod to have a negative charge.
When a neutral and non-polarized conducting rod moves through a magnetic field, it will experience a force known as the Lorentz force. This force acts on the moving charges within the rod, and causes them to move perpendicular to both the direction of motion and the magnetic field. In this case, since the rod is moving to the right, and the magnetic field is pointing into the screen, the Lorentz force will act upward on the positively charged particles within the rod. This motion will cause a separation of charges in the rod, with the top having a positive charge and the bottom having a negative charge.
Explain why omebody would ue a panner with a longer handle if they needed to undo a tight bolt
A spanner with longer handle increases the torque which in turn requires less force to undo the bolt.
This is because the rotational effect of a force depends on the perpendicular distance of the line of action of the applied force from the axis of rotation. The greater the vertical distance, the less force is required to rotate the body. That's why a spanner has a long handle. Long handles relieve pressure due to increased surface area. A long handle wrench is recommended. The larger the area, the lower the pressure, and the larger the area, the lower the pressure. The longer the handle, the greater the torque, and it will be easier to open a stuck bolt with a certain amount of force.
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The temperature of 7. 33 moles of a diatomic gas is raised from 44. 4 degrees celsius to 71. 9 celsius. What was the "change in the internal energy" of the gas?
(unit = j)
The change in the internal energy of the gas is found as 4189.6 J.
Explain the term internal energy?internal drive U is the sum of the kinetic energy brought about by the molecular motion and indeed the potential energy brought about by the vibrational motion as well as electric energy the atoms among molecules in a system or perhaps a body with clearly defined limits.
We need to understand the work done through expansion and the quantity of heat transfer in order to compute the change of internal energy of a gas. We really need volume change to compute the amount of work completed. Therefore, we begin by computing the change in volume.We will consider the gas to just be perfectly ideal.
Change in volume,
∆V= n* R*( T2 - T1)/ P
∆V = 7.33 * 0.082* 27.5 K/ 1
∆V = 16.53 L
Now,
Work done for expansion,
W = - P*∆V = - 1 atm* 16.53 L
W = - 16.53 L atm
W = -16.53 L atm * (8.314 J/0.082 L atm)
W = - 1676 J
(0.082 L atm = 8.314 J)
Heat transfer, Q = n* Cp*(T2 - T1)
Q = 7.33* 3.5*8.314* 27.5
Q = 5865.6 J
We know that, Cp = 3.5*R, if diatomic gas
As per first law of thermodynamics,
∆E = Q + W = 5865.6J - 1676 J
∆E = 4189.6 J
Thus, the change in the internal energy of the gas is found as 4189.6 J.
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How many years older will you be 2. 00 billion seconds from now? (Assume a 365-day year. )
After 2.00 billion seconds you will be around 63 years assuming a 365 day year.
To know the answer you need to know the number of seconds in a year.
First, you need to multiply, 60 × 60
to find the number of seconds in an hour, which is 3600 seconds.
Then, multiply = 3600 × 24
to find the number of seconds in a day, which is 86,400 seconds.
Next, multiply = 86400 × 365
to find the number of seconds in a year, which is 31,536,000 seconds.
Finally, divide 2,000,000,000 by 31,536,000 and you will get about 63 years.
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55. Cars A car moves 65 km due east then 45 km due
west. What is its total
displacement?
Answer:
A car moves 65 km due east and then 45 km due west. The car has traveled 65 km east and 45 km west, so it has covered a total distance of 65 + 45 = 110 km.
However, the displacement is the final point minus the initial point and not the total distance traveled. In this case, the car has traveled 65 km east and 45 km west, so it is back to its initial point. Therefore, its total displacement is 0 km.
Answer: The total displacement of the car is 20 km West.
Explanation:
This is because it moved 65 km East and then 45 km West, which effectively cancels out 65-45 = 20 km of the Eastward movement.
It does not matter how much distance the car covered in total, it only matters the net distance it moved in a certain direction.
four charges are at the corners of a square, with b and c on oppositecorners. charges a and d, on the other two corners, have equal charge, while both b and c have a charge of 1.0 c. what is the charge on a so that the force on b is zero?
Charges a and d, on the other two corners, have equal charge, while both b and c have a charge of 1.0 c, so the charge so that the force on b is zero is -2.8.
Charge is the material's physical quality that results in a force being applied to it when it is exposed to an electromagnetic field. You can have a positive or negative electric charge. Opposite charges attract one another while like charges repel one another. Neutral refers to an object that carries no net charge.
A square is a geometric shape with four equal-length sides and four right-angled corners. When diagonally opposite charges are paired, the fields inside every duo cancel in examples 1 and 2, leaving no net field at the centre.
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what is the maximum distance we can shoot a dart, from ground level, provided our toy dart gun gives a maximum initial velocity of 2.78 m/s and air resistance is negligible?
If air resistance is negligible and our toy dart cannon generates a maximum initial velocity of 2.78 metres per second, we can shoot a dart up to a maximum distance of 0.74 metres from the ground.
Velocity is a time-dependent measure of how quickly an object's position changes in relation to a frame of reference. The velocity of an object indicates both its direction and speed of motion. Final velocity is a vector quantity that describes the speed and direction of a moving body after it has reached its maximum acceleration. The relationship between two points in physical space is given by the formula R = v2 sin2 theta/g.
R(max) equals v2/g if theta is 45 degrees.
R = 2.7^2 / 9.8 = .74 m
R = v^2 sin 2 theta / g
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a horizontal force of 110 n is applied to a stationary wooden box in one direction, and a 700 n horizontal force is applied in the opposite direction. what additional force (in n) is needed for the box to remain stationary?
The additional force needed is 590 N.
Given,
Force of 110 N is applied in one direction and a force of 700 N is applied in other direction. In order to keep the box stationary, additional force applied is difference between the two applied forces.
i.e. Additional force = 700N - 110N = 590N
Push or pull of an object is considered a force. Push and pull come from the objects interacting with one another. Terms like stretch and squeeze can also be used to denote force.Force is an external agent capable of changing a body’s state of rest or motion. It has a magnitude and a direction. The direction towards which the force is applied is known as the direction of the force, and the application of force is the point where force is applied.In the standard international system of unit (SI unit) it is expressed in Newton (N).The quantity of force is expressed by the product of mass (m) and acceleration (a). The equation or the formula for force can mathematically be expressed in the form of: F = ma.To k now more about force visit :
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A company uses drones to fly food to people in regions that
have experienced natural disasters. The food is packed in
boxes that are attached to parachutes. How can the
company change the design of its parachute to reduce the
number of boxes that are damaged when they hit the
ground? (1 point)
The company can design a heavier parachute.
The company can design a smaller parachute.
The company can design a lighter parachute.
The company can design a parachute with more surface
area.
The parachute would be made to be heavier and more efficient. Option A
How can the parachute be redesigned?
We know that the way that the parachute functions would be related to the way that it is designed. We have to know that if the parachute is heavy, it is going to take a shorter time for the parachute to reach the ground because the air resistance would be overcome by the weight of the parachute.
For the redesign of the parachute. The best option is to ensure that the parachute us made in such a way that it is much heavy and able to travel through air easily.
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Answer: The company can design a parachute with more surface area.
Explanation: I just did the quick check and it was right!
a hypnotist's watch hanging from a chain swings back and forth every 0.43 s. what is the frequency (in hz) of its oscillation?
According to the problem the frequency of the oscillation (in hz) is 2.33 hz.
What is oscillation?Oscillation is a repetitive variation in the value of a physical quantity over time. It can involve a periodic change in the magnitude of a signal or the direction of a signal's movement. Examples include the swinging of a pendulum, the vibration of a tuning fork, the alternating current in an electrical circuit, and the periodic motion of a molecule. Oscillation is a key component of many natural phenomena, from ocean waves to the beating of a human heart. It is also a fundamental concept in physics, engineering, and mathematics. Oscillation is essential for the operation of numerous mechanical and electronic systems, from motors and generators to cell phones and radios.
The frequency of the oscillation (in hz) is 2.33 hz.
This is because frequency is equal to the inverse of the period (time) of the oscillation.
The period of the oscillation is 0.43 s, so the frequency is calculated by taking the inverse of 0.43 s,
which is 2.33 hz.
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Which et of condition would promote the greatet temperature change from unrie to mid-afternoon?
The combination of cloudy skies, quiet winds, and humid air would encourage the greatest temperature shift from sunrise to mid-afternoon.
The location of a place in relation to the sea is the primary factor that affects temperature. Compared to land, the sea both gains and loses heat gradually. Rapid warming and cooling occur on land.
Latitude, height, distance from the sea, and ocean currents are the four unavoidable factors that affect temperature.
Compared to land, oceans warm up and cool down considerably more gradually. This indicates that, for the same latitude and elevation, coastal areas tend to be warmer in the winter and cooler in the summer.
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The greatest temperature change from sunrise to mid-afternoon would be caused by a mix of gloomy skies, calm winds, and humid air.
The main factor affecting temperature is where a place is in proximity to the sea. The sea progressively warms and cools compared to land. On land, there is a sudden warming and cooling.
The four unavoidable factors that affect temperature are latitude, height, distance from the sea, and ocean currents. Oceans warm up and cool down much more gradually than land does. This shows that coastal places typically experience warmer winters and cooler summers for the same latitude and elevation.
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An object moves from point x to point y in 20 s, where the velocity at x = 50 km/h and
the velocity at y = 5. 56 m/s, so the acceleration of this object is.
The acceleration of this object is [tex]-8.33 m/s^2[/tex] (negative acceleration means it is slowing down).
How to calculate the acceleration of an object?To calculate the acceleration of an object you can use the following formula:
a = (v_f - v_i) / t
where a is acceleration, v_f is final velocity, v_i is initial velocity, and t is time.
Velocity at x = 50 km/h and velocity at y = 5.56 m/s, and the time taken to move from point x to point y is 20 seconds, so plug these values into the formula to get the acceleration: can ask. :
a = (5.56 m/s - (50 km/h)*(1000 m/km)/(3600 s/h)) / 20 seconds
a = (5.56m/s - 13.89m/s) / 20s
a = -8.33m/s^2
So the acceleration of this object is -[tex]8.33 m/s^2[/tex] (negative acceleration means it is slowing down).
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If a heat engine is operating between two temperatures (QH > Qc), what is the maximum efficiency attainable?
The maximum efficiency attainable for a heat engine operating between two temperatures (QH > Qc) is determined by the Carnot efficiency.
The Carnot efficiency represents the maximum theoretical efficiency that can be achieved by any heat engine operating between two temperatures. The formula for the Carnot efficiency is:
Efficiency = (Qc / QH) / 1.
where Qc is the engine's heat absorbed from the cold reservoir and QH is the engine's heat rejected by the hot reservoir.
It is important to note that for a heat engine to reach Carnot efficiency, it must operate in a reversible manner; in other words, it must be able to run in a cycle that can be reversed without any loss of energy. In practice, it is difficult to achieve Carnot efficiency in real-world heat engines due to the presence of friction and other inefficiencies.
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after a glass rod is rubbed against a silk cloth, the glass rod has a charge of 5 and the silk cloth has a charge of -7. what coule the original charges of the glass rod and silk cloth have been?
while the fabric is negatively charged, becoming positively charged. The opposing charges that two objects get when they brush against one another are explained. according to convention law.
Does the friction created whenever a glass rod is brushed with a silk fabric cause the glass rod to become positively charged?Because electrons are transported from the glass to the silk when a silk cloth is stroked across a glass rod, opposing charges are observed on both. Charge is neither generated nor destroyed during this procedure. Simply said, it is passed through one body to the other. The conservation law of charge therefore agrees with this observation.
Does the mass of a glass rod change when silk is rubbed across it?We are aware of the mass that electrons have. Therefore, when we remove some electrons from of the body, it will become positively charged and lose mass. Consequently, when a silk is brushed on a glass rod.
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An enormous amount of electricity is created at power-generating stations and sent across the country through wires that carry high voltages. Appliances, power lines, airport and military radars, substations, transformers, computers, and other equipment that carries or uses electricity all generate electromagnetic fields.
Many questions have been raised about how electromagnetic fields affect our bodies. Do they pose a public health risk? Perform an Internet search to find information about the effects of electromagnetic fields on public health. Then, discuss the pros and cons of using equipment that produces an electromagnetic field.
Here is one authoritative source to get you started: electromagnetic fields and public health
An internet search to find information about the effects of electromagnetic fields on public health is highly dangerous to humans and other living organisms.
What do you mean by Electromagnetic fields?Electromagnetic fields may be defined as a combination of invisible electric and magnetic fields of force. They are typically generated by natural phenomena like the Earth's magnetic field but also by human activities, mainly through the use of electricity.
Electromagnetic fields highly impact numerous members of the public and have attributed a diffuse collection of symptoms to low levels of exposure to electromagnetic fields at home. Reported symptoms include headaches, anxiety, depression, nausea, fatigue, and loss of appetite.
Moderate to high Exposure to magnetic fields is strong enough can lead to dizziness, seeing light flashes, and feeling tingling or pain through stimulation of nerves. Exposure to radiofrequency fields that are strong enough can lead to the heating of body tissue, and result in damage to tissues and organs.
Therefore, an internet search to find information about the effects of electromagnetic fields on public health is well described above.
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A 68.5 kg rocket is to be launched upwards with an acceleration of 3.65 m/s^2. What is the size of the net force acting on the rocket?
Answer:
250.025 Newtons
Explanation:
Fnet=ma
a 8.4 kg object is on mars, where the gravitational field strength is 3.7 n/kg. what is the object's weight in newtons?
31.08 N will be the weight of that object on mars which has a mass of 8.4 kg as the gravitational field strength is 3.7 n/kg on Mars.
As we know that weight is nothing just force a body exerts on the surface so in a similar way the weight will be mass* acceleration due to the planet(Mars in this case) (g) which is 3.7 n/kg given. So
W = mass* g
w = 8.4 * 3.7 => 31.08N
Each planet has different gravitational field strength that we call (g) in the case of earth it is calculated as 9.8 n/kg but generally, we take as 10 n/kg for simplifying the calculation, and Mars has 3.7 n/kg and moon has as just 1.4 n/kg.
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As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. There is no one around to help, so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. You pull up on the rope to lift the box. A) Once you have pulled hard enough to start the box moving upward, what is the magnitude F of the upward force you must apply to the rope to start raising the box with constant velocity? Express the magnitude of the force in terms of m, the mass of the box. F = 4. 9 m? b) Part B Consider lifting a box of mass m to a height h using two different methods: lifting the box directly or lifting the box using a pulley (as in the previous part). What is Wd/Wp, the ratio of the work done lifting the box directly to the work done lifting the box with a pulley? Express the ratio numerically.
Answer:
When you pull with a force upward so that the box is just about to rise, the sum of the two tensions (one from the ceiling and one from your hands pulling) equal the weight of the box. Thus C + H = W; where C is the ceiling rope tension and H is the hand rope tension. W = mg, the weight of the box.
Because there is no mechanical advantage in the single pulley, C = H, the two tensions are equal. So, we can write 2H = W = mg; and thus, H = W/2 = mg/2 when the box is just about to rise. To raise the box, you must have 2H>W; so that H > W/2 which means you need to yank upward on the rope in your hand with a force H (your F) just a bit over half the weight of the box.
Now here’s the tricky part. Once you’ve gotten the box to accelerate (start moving), you can relax the force H a bit so that it exactly equals H = W/2. Why? Because by keeping the net force f = ma = W – 2H = 0, acceleration settles in at a = 0 and the box is neither speeding up nor slowing down. It is then at constant velocity, which is what you specified.
Lesson here is that it takes a bit more force to get something to start moving, but once it starts to move we need to slack off a bit to maintain a constant velocity (too much force and it continues to speed up, too little and it slows down).
PS: Your question starts off with “Energy” then you talk and ask about force. They are not the same thing. I recommend you read up on the differences between energy and force. That will avoid a lot of confusion in future physics studies.
Explanation:
.
If the Earth's sideways velocity could be suddenly stopped to zero, how would Earth move?
Group of answer choices
More information is needed to answer this question
It would fall directly into the sun
It would continue to orbit as before
It would fly off into space
If the Earth's sideways velocity becomes zero the Earth would still continue to orbit as before.
Sideways velocity of the earth is the rotational speed of the earth in terms of linear velocity. That is 1100 miles an hour approximately. If the sideways velocity of the earth becomes zero, objects on the earth will start flying eastward. This is due to the momentum possesses by the object on the surface of the earth. Flying of the rocks and oceans would cause the earthquakes and tsunamis. But there will not be any effect on the orbital velocity of the earth as it is governed by the gravitational force between the earth and the sun. Which ultimately depends on the masses of the sun and the earth and the distance between them.
So the correct option will be that the earth would continue to orbit as before.
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relief supplies are being dropped to flood victims from an airplane flying horizontally at a speed v. if the airplane is at an altitude of h above the ground, what distance d in front of the landing site should the supplies be dropped?
The distance d in front of the landing site should the supplies be dropped is v√(2h/g) meter. If the horizontal velocity of the airplane is v m/s and height of the plane from the ground is h.
Horizontal velocity of the airplane = v
height of the airplane = h
Initial velocity of the food, u = 0 m/s
From the second equation of motion,
S = ut +0.5gt²
h = 0.5gt²
t = √(2h/g)
It is time taken by the food to reach the ground. in this time the horizontal distance travelled by the food is, d = v × t
d = v × √(2h/g)
d = v√(2h/g)
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a diver moves horizontally from the underside of a bridge structure (position 1) to open water (position 2). ignoring effects like currents in the water, what pressure change will the diver sense between positions?
Option -C : Pressure stays the same because it is only a function of depth .
When the diver moves horizontally, the pressure is unaffected as pressure is function of depth only.
since,
p = denisty × gravity × depth
so only depends on depth.
The molecules and atoms that make up the many layers of the atmosphere are continually moving in arbitrary directions. Despite their small size, when they hit a surface, they apply pressure that humans perceive as a force. Since molecules can flow in any direction, they can even apply air pressure to an object as they collide from below. Air pressure can be applied in all directions in the atmosphere. An object or person suspended in a fluid and moving with it experiences static pressure. The pressure that develops when a flow is isentropically slowed to zero velocity is known as the stagnation pressure. The air pressure in various environments will vary, which will have an impact on how the vehicle operates. Air is thinner at higher altitudes,
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Question :
a diver moves horizontally from the underside of a bridge structure (position 1) to open water (position 2). ignoring effects like currents in the water, what pressure change will the diver sense between positions?
A . pressure increases from 1 to 2 because the bridge keeps the atmosphere from pushing down on the water at position 1.
B . pressure decreases from 1 to 2 because the weight of the bridge pushes down on the water at position 1.
C. Pressure stays the same because it is only a function of depth .
D. pressure may increase or decrease depending upon water properties like density.