Answer:
Explanation:
Given:
L = 881.0 m
F = 28.0 N
___________
A - ?
The work :
A = L*F = 881.0 * 28.0 ≈ 24 670 J
Which is true of diffraction?It does not occur for light.It does not occur for sound. It occurs best when the slit width is less than the wavelength of a wave.
Diffraction is the change in a wave's direction as it travels around barriers. Diffraction is observed in both light and sound waves. This means that options 1 and 2 are wrong.
For any opening or slit, waves with longer wavelengths bend more than waves with shorter wavelengths. If the wavelength is smaller than the opening, it would be difficult for diffraction to occur. Thus, the correct option is
It occurs best when the slit width is less than the wavelength of a wave.
Laser light passing through two small slits produces a bright fringe centered at the midpoint on a distant screen because.
Laser light passing through two small slits produces a bright fringe centered at the midpoint on a distant screen because the light waves travel the same distance from each slit to the midpoint.
What are light waves?Because it is composed of magnetic and electric fields, light frequently exhibits wave behavior and is thus categorized as such an electromagnetic wave. Magnetic fields are perpendicular to each other and fluctuate perpendicular to the wave propagation direction. These are referred to as transverse waves as a result.
What materials make up a light wave?Photons are discrete energy packets that make up light. Photons move at the speed of light, possess momentum, and lack mass. Light possesses both wave-like and particle-like properties.
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an old chrysler with mass 2050 kg is moving along a straight stretch of road at 75 km/h. it is followed by a ford with mass 1300 kg moving at 40 km/h. how fast is the center of mass of the two cars moving?
the center of mass of the two cars moving is with a speed of 61.41m/s
What is center of mass ?
A position established in relation to an object or set of objects is the center of mass. It represents the system's average location as weighted by each component's mass. The centre of mass for straightforward stiff objects with homogeneous density is found at the centroid.
The center of mass also functions as a location at which inertial forces, such as centrifugal force, and gravitational force are applied. There are a number of direct and indirect techniques for locating the center of mass.
Let mc be the mass of the Chrysler and νc be its velocity .
Let mf be the mass of the Ford and νf be its velocity . Then the velocity of the center of mass is
ν com = (mc v c + mf v f) /m c+ m f = [tex](2050*75 + 1300*40)/(2050+1300)[/tex]
= 61.41 km/h
We note that the two velocities are in the same direction, so the two terms in the numerator have the same sign.
the center of mass of the two cars moving is with a speed of 61.41m/s
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a tourist being chased by an angry moose is running in a straight line toward her car at a speed of 4.6 m/s. the car is a distance d meters away. the moose is 46.5 m behind the tourist and running at a speed of 10.8 m/s. the tourist reaches her car safely. what is the maximum possible value for d in meters?
A tourist was chased by a moose and run toward her car at a speed of 4.6 m/s. As the tourist reaches her car safely, the maximum possible value of the distance between her and the car was 34.5 m
Formula:
s = v . t
Where:
s = distance
v = velocity
t = time
The tourist reached her car safely means at minimum she had the same time with the moose to reach the car.
Tourist circumstance:
distance = d
v = 4.6 m/s
time to reach the car:
t_tourist = d / 4.6
Moose circumstance:
distance = d + 46.5
v = 10.8
time to reach the car:
t_mouse = (d + 46.5) / 10.8
t_tourist = t_mouse
d / 4.6 = (d + 46.5) / 10.8
(10.8 - 4.6) d = 46.5 × 4.6
6.2 d = 213.9
d = 34.5 m
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an elevator of mass m is initially at rest on the first floor of a building. it moves upward, and passes the second and third floors with a constant velocity, and finally stops at the fourth floor. the distance between adjacent floors is h. what is the net work done on the elevator during the entire trip, from the first floor to the fourth floor?
From the first floor to the fourth floor, the elevator's net work during the entire trip is -3mgh.
Given,
On the first floor of a building, an elevator with mass m is initially at rest. It ascends at a constant speed, passing second and third floors before coming to a stop at the fourth floor.
the separation between the floors is h
The distance from the first floor to the fourth floor Equals 3 hours of work = -mg(3 hours)
= -3mgh
Work Done = -3mgh
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22. Determine If you walked 20 m, took a book from a library table, turned around and walked back to your seat, what are the dis tance traveled and displacement? please answer in full sentences
Answers:
Distance = 40 meters
Displacement = 0 meters
============================================
Reason:
The distance traveled is simply the sum of the two distances 20 and 20 to get 20+20 = 40. It's what anyone would expect when they ask "how far did the person travel in total?"
The displacement is the change in position from start to end. In this case, the student ends up back where they started, meaning no change has happened. If the teacher closed their eyes and opened them after the student gets back, then for all the teacher knows, the student hasn't moved at all.
Put another way, displacement tells us how far away the student has ended up compared to the start position. But since they went back to the start, no change has occurred.
at an amusement park there is a ride in which cylindrically shaped chambers spin around a central axis. people sit in seats facing the axis, their backs against the outer wall. at one instant the outer wall moves at a speed of 3.09 m/s, and an 70.2 kg person feels a 560 n force pressing against his back. what is the radius of a chamber?
At an amusement park there is a ride in which cylindrically shaped chambers spin around a central axis and the radius of a chamber r= 0.387 m
Given
Mass of the person m = 70.2 kg
speed v = 3.09 m/s
Force F = 560N
-------------------------------------------
We have the formula for the force is given by
F = ( mv2) /r
The radius of the chamber is given b y
r = ( mv2) /F
= ( ( 70.2 kg)(3.09 m/)2) /(560N)
r=0.387 m
A circle's or a sphere's radius is the distance along a line connecting its centre and perimeter. From any point on the circle's or sphere's circumference to the centre, the radius' length is constant. Its length is halved by its diameter. The radius is a line segment connecting the centre of a circle or sphere to its perimeter or boundary in geometry.You'll require more effort as you reduce the radius because you're dividing by a lower force.
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select the best answer. the logarithmic decrement is: a. the ratio of the damping in the system to the critical damping b. the ratio of the successive amplitudes in a time series c. the ratio of the damping in one system compared to another system d. the total damping present in the system
Logarithmic decrement is the ratio of successive amplitudes in a time series.
The logarithmic decrement δ is equal to the natural logarithm of the ratio of two successive maximum deflections x of oscillating quantity in the same direction:
δ = log( [tex]x_{1} /x_{2}[/tex])
Logarithmic decrement is used to find the damping ratio of an underdamped system in the time domain. It is defined as the natural logarithm of the ratio of any two successive amplitude on the same side of the mean line.
Therefore we get that logarithmic decrement is the ratio of successive amplitudes in a time series.
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in a crash, rear seat passengers in a car a. can fly forward with incredible force, injuring or killing passengers in the front seat. b. are usually protected by the front seat. c. are more protected due to their distance from the impact point. d. all of the above
In a crash rear-seat passengers in a vehicle can fly ahead with first-rate force injuring or killing passengers in the front seat. Option A.
There is a common misconception that people are safer in the back seat, but the reality is that rear-seat passengers who are not buckled up are more likely to die in a crash. Upon impact, they're often thrown forward into the back of front seats with significant force. Sit upright and you will have the least chance of getting an auto injury.
It will keep you secure and will lower your risk for serious injury. Headrests also protect you in the event of an accident. consistent with a recent study by the Insurance Institute for Highway Safety IIHS the back seat is no longer the safest place. In fact, sitting in the front seat increases your chances of surviving a car accident.
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the cliff divers of acapulco push off horizontally from rock platforms about 35 m above the water, but they must clear the rocky outcrops at water level that extend out into the water 5 m from the base of the cliff directly under their launch point. what minimum speed is necessary to clear the rocks? how long are they in the air?
The minimum speed necessary for the diver to clear the rocks 10.59m/s and the diver will be in air for about 2 seconds.
From the provided situation, we can analyze that the path of travel of the diver will be a projectile.
The maximum horizontal range is 35 meters.
And the height required is 5 meters.
We know, for a projectile,
Horizontal range R is given by U²sin(2A)/g
The height H attained is given by U²sin²A/2g
Dividing the height by range,
H/R = tanA/4
TanA = 20/7
Now, we can find,
SinA = 21.18
We know,
H = U²sin²A/2g
U²=2Hg/Sin²A
U²=2(5)(10)/(20/21.18)²
U = 10.59m/s.
The diver should start with speed of 10.59m/s to clear the rocks.
The time of flight is given by,
T = 2UsinA/g
Putting the values,
T = 2(10.59)(20/21.18)/10
T = 2 seconds.
The diver will be in air for 2 seconds.
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a nonmechanical water meter could utilize the hall effect by applying a magnetic field across a metal pipe and measuring the hall voltage produced. what is the average fluid velocity (in m/s) in a 3.00 cm diameter pipe, if a 0.550 t field across it creates a 60.0 mv hall voltage? m/s
The average fluid velocity (in m/s) is 3.636 m/s.
The volume of fluid moving past a spot in a given amount of time is measured as the flow rate. Circular and noncircular pipelines both experience fluid flow in daily life.
From the question we have given:
The diameter of the pipe (l) is 3.00 cm or 0.0300 m.
The magnetic field (B) is 0.550 T.
The hall voltage (E) is 60.0 mv or 60 x 10⁻³ v.
[tex]v = \frac{E}{Bl}[/tex]
The average fluid velocity can be calculated using the equation E = Blv.
In this instance, the width really corresponds to the diameter:
[tex]v = \frac{E}{B * l}[/tex][tex]v = \frac{60 \;* \;10^{-3} \; V}{0.550 \;T \;*\; 0.0300 \;m} \\[/tex][tex]v = \frac{60 \;*\; 10^{-3} \;V}{0.0165\; m} \\[/tex]
[tex]v = 3.636 \;m/s[/tex]
Thus, the average fluid velocity is 3.636 m/s.
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If a car travels 1,000 m in 60 seconds how fast is it going?
Answer:
see below
Explanation:
1000 m / 60 s = 16 2/3 m/s
You are driving at the speed of 29.5 m/s
(66.0037 mph) when suddenly the car in
front of you (previously traveling at the same
speed) brakes and begins to slow down with
the largest deceleration possible without skidding. Considering an average human reaction,
you press your brakes 0.558 s later. You also
brake and decelerate as rapidly as possible
without skidding. Assume that the coefficient
of static friction is 0.708 between both cars’
wheels and the road.
The acceleration of gravity is 9.8 m/s
2
.
Calculate the acceleration of the car in front
of you when it brakes.
Answer in units of m/s
2
.
What is the frictional force acting on the
35 kg mass?
Answer in units of N
Answer:
honestly not sure what to do good luck though
The element lanthanum has an isotope with an atomic mass of 138. 9 amu and an abundance of 99. 91%. A second isotope has an atomic mass of 137. 9 amu and an abundance of 0. 9%. What is the average atomic mass of lanthanum?.
Considering the definition of atomic mass, isotopes and atomic mass of an element, the average atomic mass of lanthanum is 151.186 amu.
Definition of atomic massThe atomic mass is obtained by adding the number of protons and neutrons in a given nucleus of a chemical element.
Definition of isotopeThe same chemical element can be formed by different atoms, that is, their atomic numbers are the same, but the number of neutrons is different, thus generating the isotopes of the element.
Definition of atomic massThe atomic masses of chemical elements are usually calculated as the weighted average of the masses of the different isotopes of each element, taking into account the relative abundance of each of them.
Atomic mass of the element in this caseIn this case, you know:
The first isotope has an atomic mass of 138.9 amu and an abundance of 99.91%.The second isotope has an atomic mass of 137.9 amu and an abundance of 0.09%.The average mass of lanthanum can be calculated as:
average mass of lanthanum= 138.9 amu×0.9991 + 137.9 amu×0.09
average mass of lanthanum= 151.186 amu
Finally, the average atomic mass of the element in this case is 151.186 amu.
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6. What is the acceleration of a 15 kg object being pushed with 200 N of force?
The acceleration of the object will be 13.33 m/s^2.
According to Newton's second law of motion,
The magnitude of Force is equal to the product of the mass of the body and the acceleration it is given ( or achieves ).
The units of force, mass and acceleration are Newton, kg and m/s^2 respectively.
In numerical terms,
Force = mass × acceleration
i.e. F = m × a
Given,
mass of the body = 15 kg
Force applied to the body = 200 N.
Putting these values in the equation,
200 = 15 × a
=> a = 200/15
=> a = 13.33 m/s^2.
Therefore, the acceleration of the given body will be 13.33 m/s^2.
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When a red hot piece of iron is put into boiling water what happens to the temperature of the water
Answer:
The temp of the water will remain the same...BUT some of the water will be converted to steam
Explanation:
Boiling water has reached its max temperature of liquid state....adding more heat will create steam ...at a constant water temp
the chapley-curtis debate concerned the location of the chapley-curtis debate concerned the location of the milky way galaxy. center of the universe. the sun within the milky way galaxy. spiral nebulae.
Yes , Astronomer Edwin Hubble was able to determine the distance .
What is Shapley-Curtis debate ?
The dispute between Shapley and Curtis centered on the existence of other galaxies, with Curtis asserting the existence of other galaxies and Shapley asserting that the other nebulae observed were part of the Milky Way. The argument came to a final conclusion when Hubble was able to show that the Andromeda galaxy is over a million light years away and not part of our galaxy. We were able to determine the distance to a variable star in the Andromeda galaxy more than a year away.
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Compare and contrast an active solar heating system with a radiator system
There are two types of solar system was there:
Active solar systemPassive solar system.What is solar system?One system that is energies with sunlight. In other words which convert the sun energy in other energy is called solar system. It made with silicon.
What is the difference between an active solar heating system with a radiator system?As we mentions earlier there are two types of solar system was their,
Active solar system.Passive solar system.Active solar system: This system made with silicon bar which excites by absorb the sunlight and excites by it. It can change energy between any energies and help others to grow more. It helps to make machines to make hot water and electricity and many more. It is not cost friendly. The costs for such custom systems range from $3,000 to $10,000 depending on the size of the space.
Passive solar system: This system is very much cost sufficient solar energy generator. This energy displace the extra things like electricity, natural gas, or other systems. It so cost friendly that by installing big windows and tress it can hold energy in day and release energy at night. This is called the radiator system as it radiates energy at night.
According to the discussion, this is the main difference between the an active solar heating system with a radiator system.
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a toaster is designed to operate with a voltage of 120 v, and a clothes dryer is designed to operate with a voltage of 240 v. based solely on this information, which appliance uses more power?
Answers are impossible given the information provided.
P=VI, P=VI, where V is the voltage, I is the current, and P is the power, gives the power in an electric circuit.
We cannot draw any conclusions from the voltage measurement alone because power depends on both voltage and current. The information provided is therefore insufficient.
Answers are impossible given the information provided.
Describe voltage.A lamp can be lit when charged electrons (current) are compelled through a conducting loop by the pressure of an electrical circuit's power source. In a nutshell, voltage equals pressure and is expressed in volts (V).
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Predict what will happen when the bicep muscle exerts force on the lower arm bone.
Answer:
the soft drink will be elevated by the lower arm
Explanation:
firstly, muscles can only pull on bones to cause movement so if the bicep applies force on the lower arm bone, it will pull it up.how do astronomers measure that sunspots come in north pole / south pole magnetic pairs? how do they view the sun's magnetic field? from helioseismology and doppler shifts spectral lines can be split into multiple lines, further apart the stronger the magnetic field is from neutrino telescopes revealing where the proton-proton chain is broken from the motion of iron filings naturally streaming out of the radiation zone
The Zeeman effect, a feature of atoms, is used to quantify the solar magnetic field. To do this, scientists look at the spectral lines that originate from sunspots and calculate by how much these lines are split.
The Zeeman effect is the result of a spectral line splitting into many components when a static magnetic field is present. It bears the name Pieter Zeeman after the Dutch physicist who made the discovery in 1896 and won the Nobel Prize for it. The magnetic dipole interaction between the nuclear spin moment and the internal magnetic field at the nucleus is what causes magnetic splitting (also known as the nuclear Zeeman effect). Three different varieties of the Zeeman Effect can be seen: the standard Zeeman effect, the anomalous Zeeman effect, and the diamagnetic Zeeman effect. The Zeeman effect is the splitting of atomic energy levels caused by an external magnetic field. This effect is also known as the Bohr's Magneton and is further characterised by orbital and spin angular momentum.
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a ball on the end of a string is whirled around in a horizontal circle of radius 0.300 m. the plane of the circle is 1.40 m above the ground. the string breaks and the ball lands 1.50 m (horizontally) away from the point on the ground directly beneath the ball's location when the string breaks. find the radial acceleration of the ball during its circular motion.
Radial acceleration of the ball during its circular motion is 41.8 m / s².
a = v ²/ r represents the circular motion acceleration.
In addition, they provide the X and Y positions at which the body will fall if the rope breaks.
x = v₀x t,
y = v₀x t-1/2gt²
because the circle is horizontal, the value of v0x is zero (v0x = 0).
X = v₀x t
t = x / v₀x
y = - 1/2 g t²
In order to determine the initial velocity on the X axis, let's replace it with y = − 12 g (x / vox) ²
v₀ₓ = √ [ (9.8) 1.6² / (21)]
v₀ₓ = 3.54 m / s
Its circle is in a horizontal position, so in addition to being the horizontal velocity, this is also the velocity of the body at the point of rupture.
The radial acceleration is now calculated using the formula
a = v² / r
a = 3.54² / 0.300
a = 41.8 m / s²
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The speed of sound depends on all of the following properties except:
a
Type of element
b
Composition of the medium or type of matter
c
Density
d
Temperature
Answer:
d: temperature
Explanation:
temperature doesn't have anything to do with sound
wake turbulence is near maximum behind a jet transport just after takeoff because a. of the high angle of attack and high gross weight. b. the engines are at maximum thrust output at slow airspeed. c. the gear and flap configuration increases the turbulence to maximum.
Wake turbulence is near maximum behind a jet transport just after take off because of the high angle of attack and high gross weight.
Explanation:
Every aircraft generates wake turbulence while in flight. Wake turbulence is a function of an aircraft producing lift, resulting in the formation of two counter-rotating vortices trailing behind the aircraft.
Wake turbulence from the generating aircraft can affect encountering aircraft due to the strength, duration, and direction of the vortices. Wake turbulence can impose rolling moments exceeding the roll-control authority of encountering aircraft, causing possible injury to occupants and damage to aircraft. Pilots should always be aware of the possibility of a wake turbulence encounter when flying through the wake of another aircraft, and adjust the flight path accordingly.
Wake turbulence is near maximum behind a jet transport just after take off because of the high angle of attack and high gross weight.
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a 7.26 kg bowling ball and a 0.163 kg cricket ball are simultaneously dropped from a height of 10.0 m. what can you say about the velocity of the bowling ball, vb, compared to the velocity of the cricket ball, vc, when they hit the ground?
The velocity Vb of the bowling ball will be same as that of the cricket ball when dropped simultaneously from the same height. Because the velocity while hitting the ground is not dependent of mass.
Let us consider a general case,
Let us say the ball is dropped from a height H, its final velocity on reaching the ground is V, the acceleration g will be constant because everything is happening on the earth's surface and neglecting the air drag,
So, using equation of motion,
V ²-U²=2gH
U is the initial velocity in of the ball which is zero in our case,
So,
V²=2gH
V =√2gH
As we can see, the velocity on hitting the ground is independent of the mass.
So we can say,
Vb of the balling bowl is same as that of Vc on hitting the ground.
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1. a circular coil 0.0500 m in radius, with 30 turns of wire, lies in a horizontal plane. it carries a counterclockwise (as viewed from above) current of 5.00 a. the coil is in a uniform 1.20 t magnetic field directed toward the right. find the magnitudes of the magnetic moment and the torque on the coil.
Magnetic moment of the given coil is 1.178 Am²
Torque of the given coil is 1.414 TAm²
Radius of the coil = 0.05 m
Number of turns in the coil = 30 turns
Current passing through the coil = 5 A
Magnetic field in the coil = 1.2 T
The current flows in counterclockwise direction. Therefore by thumbs rule, the magnetic field flows towards right side.
The magnetic moment of the coil
M = N x I x A
where N is the number of turns in the coil
I is the current passing through the coil
A is the area of the coil
Let us substitute the known values in the above equation,
M = 30 x 5 x πr²
= 30 x 5 x 3.14 x (0.05)²
= 471 x 0.0025
= 1.178
The magnetic moment of the given coil is 1.178 Am²
The torque of the coil can be found using
τ = M x B
where M is the magnetic moment and
B is the magnetic field produced due to the coil.
τ = 1.178 x 1.20
= 1.414 TAm²
Therefore , the torque of the coil is 1.414 TAm²
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two automobiles, each of mass 800 kg , are moving at the same speed, 18 m/s , when they collide and stick together. at what speed does the wreckage move if one car was driving north and one east?
14.14 m/s speed does the wreckage move if one car was driving north and one east
Based on the moment of momentum conservation in the x-direction,
1000 20 = (1000 + 1000) yields v _y v y = 10 m/s.
result = 14.14 m/s
What makes momentum so crucial?An object's mass, velocity, and direction are all related by momentum. Force arises from any change in momentum. In order to ascertain the force exerted on the item, a change in momentum is utilised.
Force and momentum are distinct even though they appear to be the same physical quantity. Whether a body is being pulled or pushed, force is often defined as an outside action. The measure of how much motion there is inside a moving body is called momentum, on the other hand.
Unlike force, which refers to a push or pull action, momentum refers to the amount of motion in a moving body. Force modifies a body's momentum. While momentum varies while acceleration is constant, force does not.
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to negotiate a flat (unbanked) curve at a faster speed, a driver puts a couple of sand bags in his van aiming to increase the force of friction between the tires and the road. will the sand bags help?
Given the fact that the friction between the van and the road would increase, then the sand bags would help.
What is friction?The term friction has to do with the force that opposes the movement of an object on another. This in a sense implies that the frictional force is a resistive force. It can help to slow an object down and this is why the braking system of a car operates on the principle of friction.
Now, we are told that to negotiate a flat (unbanked) curve at a faster speed, a driver puts a couple of sand bags in his van aiming to increase the force of friction between the tires and the road.
The task is to determine if the sand bags would be of help. We have to note that the sand bags would help to increase the friction between the car and the road so it would definitely be of help.
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If net force acting on object is 0, then the force is considered to be..
a. balanced
b. equal in direction
c. unbalanced
d. distance/time
If net force acting on object is 0, then the force is considered to be balanced (option A).
What is net force?A net force refers to the sum of all the forces acting on an object.
The net force can accelerate a mass. Some other force acts on a body either at rest or motion. The net force is a term used in a system when there is a significant number of forces.
Fnet = F₁ + F₂ + F₃.............+ Fn
When the net force of an object is zero (0), this means that the sum of forces acting on the object is balanced. A balanced forces are forces that are opposite in direction and equal in size.
Therefore, a net force of 0 is a balanced force.
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A woman of mass 57.6 kg is standing in an elevator.If the elevator floor pushes up on her feet with a force of 395 N, what is the acceleration of the elevator? Assume the +y-direction to be up. Enter a negative answer if the acceleration is downward and a positive answer if the acceleration is upward.If the elevator maintains constant acceleration and is moving at 1.50 m/s as it passes the fourth floor on its way down, what is its speed 4.00 s later?
There are two forces acting on the woman: the normal force of the floor of the elevator and the weight of the woman.
First, find the weight of the woman by multiplying its mass times the acceleration of gravity:
[tex]\begin{gathered} W=mg \\ =(57.6\operatorname{kg})(9.8\frac{m}{s^2})=564.48N \end{gathered}[/tex]According to Newton's Second Law of Motion, the net force acting on an object relates to the acceleration of the object according to:
[tex]\Sigma F=ma[/tex]Since the normal force of the floor is exerted upwards and the weight is exerted downwards, then:
[tex]\begin{gathered} \Sigma F=N-W \\ \Rightarrow N-W=ma \end{gathered}[/tex]Isolate the acceleration from the equation:
[tex]\Rightarrow a=\frac{N-W}{m}[/tex]Replace the values of the normal force (395N), the weight and the mass of the woman to find the acceleration of the elevator:
[tex]\begin{gathered} \Rightarrow a=\frac{395N-564.48N}{57.6\operatorname{kg}}=-2.94236\ldots\frac{m}{s^2} \\ \therefore a\approx-2.9\frac{m}{s^2} \end{gathered}[/tex]Then, the acceleration of the elevator is 2.9 m/s^2 downwards.
Use the definition of acceleration to find the final speed of the elevator 4 seconds after the initial speed of 1.50 m/s downwards:
[tex]\begin{gathered} v_f=at+v_0 \\ =(-2.94\frac{m}{s^2})(4.00s)-1.5\frac{m}{s} \\ =-13.26\ldots\frac{m}{s} \\ \approx-13.3\frac{m}{s} \end{gathered}[/tex]Therefore, the answers are:
The acceleration of the elevator is 2.9 m/s^2 downwards.
The final speed of the elevator 4 seconds after it had a speed of 1.50 m/s downwards, is 13.3 m/s downwards.