Answer:
F = -8820 N
Explanation:
Given that,
The weight of a car, W = 19600 N
Initial speed of the car, u = 30 m/s
It is brought to rest, final velocity, v = 0
Distance, d = 100 m
We need to find the average friction force acting on it.
Firstly we find the acceleration of the car using third equation of motion. Let it is a.
[tex]v^2-u^2=2as\\\\a=\dfrac{v^2-u^2}{2d}\\\\a=\dfrac{(0)^2-(30)^2}{2\times 100}\\\\=-4.5\ m/s^2[/tex]
Average frictional force,
F = ma
m is mass, [tex]m=\dfrac{W}{g}=\dfrac{19600\ N}{10\ m/s^2}=1960\ kg[/tex]
F = 1960 kg × -4.5 m/s²
= -8820 N
So, the average friction force acting on it is 8820 N.
What is the kinetic energy of a jogger with a mass of 70.8 kg traveling at a speed of 2.4 m/s?
90 points if you get it right :)
An atom of lithium (Li) forms an ionic bond with an atom of chlorine (Cl) to form lithium chloride. How are the valence electrons of these atoms rearranged to form this bond?
A few valence electrons are shared between the atoms.
Many valence electrons are shared between the atoms.
Electrons are transferred from the chlorine atom to the lithium atom.
Electrons are transferred from the lithium atom to the chlorine atom.
Answer:
electrons are transferred from the lithium atom to the chlorine atom
Answer:
D
Explanation:
I just took the test :)
A 75 kg ball carrier is running to the right at 6.5 m/s. An 80 kg defender is chasing the ball carrier running at 7.0 m/s. The defender catches the ball carrier in a completely inelastic collision. What was the kinetic energy of the ball carrier/defender system BEFORE the tackle?
Answer:
3,544.375Joules
Explanation:
Kinetic energy is the energy possessed by a body by virtue of its motion, It is expressed as;
Kinetic energy = 1/2mv²
m is the mass of the body
v is the velocity
For the ball carrier;
KE = 1/2(75)(6.5)²
KE = 3168.75/2
KE = 1584.375Joules
For the defender;
KE = 1/2(80)(7)²
KE = 3920/2
KE = 1960Joules
The kinetic energy of the ball carrier/defender system BEFORE the tackle = KE for the carrier + KE for the defender
kinetic energy of the ball carrier/defender system BEFORE the tackle= 1584.375+1960 = 3,544.375Joules
what is the function of brushes in D.C motor
Answer:
to transfer the voltage
Explanation:
The brushes make physical contact with the commutator. When a DC voltage is applied to the brushes, that voltage is transferred into the commutator which, in turn, powers the windings. This electrical input generates a magnetic field around the armature.
12. The diameter of a circle is 2.42m. Calculate its
area in proper significant figure
Answer:
A = 4.6 [m²]
Explanation:
The area of a circle can be calculated by means of the following equation.
[tex]A=\frac{\pi }{4} *D^{2}[/tex]
where:
A = area [m²]
D = diameter = 2.42 [m]
Now replacing:
[tex]A=\frac{\pi }{4} *(2.42)^{2} \\A = 4.6 [m^{2} ][/tex]
1. A race starts out at rest and accelerates to 30m/s over a period of 10s. What is the acceleration of the car?
O 3.0 m/s
O 3.0 m.s2
O 2.0 m/s2
O 5.0 m/s2
Answer:3.0m/s
Explanation:
A molecule of water H2O and a molecule of methane CH4 have close to the same mass Which statement explains why water has much higher boiling point than methane?
A. There is hoydrogen bonding between water molecules?
B. There is ionic bonding between water molecules
C. There is hydrogen bonding between methane molecules
D. There is ionic bonding between methane molecules
Answer:
A. There is hydrogen bonding between water molecules
Explanation:
Boiling point is a physical property of matter. It is typically conditioned by the intermolecular forces present between the molecules of a compound.
The nature of the intermolecular forces between the molecules of water is very different from those of methane. Water molecules have hydrogen bonds within their molecules. These intermolecular bonds are very strong compared to the london dispersion forces in methane. Hydrogen bond forms when the hydrogen of one molecule binds with the oxygen of another molecule.Answer:
A)
Explanation:
There is hydrogen bonding between water molecules
what is gravity???☺️
Answer:
Gravity
Explanation:
its an invisible force that pulls objects
toward each other.
hope it helps
Why is a teacher's feedback valuable?
Answer:
Because they could help you move on better with your strategy and ultimately get you better scores on tests
Answer:
Through feedback, teachers can provide the students with suggestions for development, learning strategies and corrections for errors. The importance of constructive feedback allows for many positive opportunities. This component also enhances a student's self-efficacy and provides an avenue for motivation.
PLEASEEE HELPPP!!!!
A mover slides a refrigerator weighing 650 N at a constant velocity across the floor
a distance of 8.1 m. The force of friction between the refrigerator and the floor is
230 N. How much work has been performed by the mover on the refrigerator?
Answer: The work is 1863 N*m
Explanation:
We can define work as:
W = F*d
Where F is the force that the mover needs to apply to the refrigerator, and d is the distance that the refrigerator is moved.
To move the refrigerator, the minimal force that the mover needs to do is exactly the friction force (In this case, the refrigerator will move with constant speed).
Then we will have:
F = 230 N
and the distance is 8.1 meters, then the work will be:
W = 230N*8.1 m = 1863 N*m
What movement allows us to move our side to side?
Answer:
Ball-and-socket joints
Explanation:
Your maximum heart rate is the maximum number of times your heart can contract in one minute
True or false
Answer:
True
Explanation:
It is true i am right
what is the uses of space weather data?
Answer:
Space Weather Data
They are used to produce forecasts, such as the monthly sunspot number forecast. Most notably, sunspot numbers represent one of the longest continuous climate records available. The data give scientists the means to make many forecasts and issue space weather advisories and alerts.
Explanation:
A single celled organism is found in a sample of water. It contains a nucleus as well as other membrane bound organelles and possesses collagen for movement. This organism most likely belongs to which kingdom?
Answer:
Explanation:
The cell is the smallest living organism that contains all the features of life, and most all life on the planet begins as a single-cell organism. Two types of single-celled organisms currently exist: prokaryotes and eukaryotes, those without a separately defined nucleus and those with a nucleus protected by a celluA single-celled organism is found living in a deep sea vent at the bottom of the ocean in extremely hot water. If it is examined further, which of the following is most likely to be found within it? It will have DNA that is not contained in a nucleus since it is likely a member of the domain Archaea.lar membrane.
PLZ HELP MEEEEEEE,;-;
Answer:
thxs for the points
Explanation:
because just started
Which way can heat never flow?
Answer:
Cold to hot.
Explanation:
Heat can never flow from cold to hot, heat transfers itself from hot to cold.
which number is larger value : 5.6*10^23 or 8.9*10^6
Need Help
Answer:
5.6*10^23. if 10^n is greater, that means its the larger value. hope dis helps
Explanation:
If clouds were made of cotton-candy what is rain
Answer:
If clouds were made of cotton candy, I think rain would be soda.
Or liquified sugar.
:)
Answer:
Liquid Sugar
Explanation:
For an example, let's look at normal clouds. They're made of water vapor, and when they rain it's because the water vapor condenses and forms a droplet heavy enough that it falls out of the sky. In both sides of the equation, they're still made out of water. So, logically, cotton candy is made almost 100% with sugar, right? All that's happened is the sugar is heated and liquified and pushed through very small holes until they cluster together and form the fluffy treat you know today. Back to the leading question, though: "If clouds were made of cotton-candy, what is rain?". Rain is the liquid form of clouds (gas), and cotton candy is the (solid) form of itself. So in order for it to rain, it needs to liquefy itself. When melted at 367°F, sugar becomes a liquid, so in that case THAT is what cotton candy would rain if it were a cloud.
≧◡≦
Mocha here! If this answer helped you, please consider giving it brainliest because I would appreciate it greatly. Have a wonderful day!
Ethics are deliberately learned from the family. Please select the best answer from the choices provided
Answer:
what are the choices provided?
Explanation:
Answer:
True
Explanation:
On Edg
Melinda is taking a tour through a new city on the tour she walk there .40 miles south 0.65 miles east 0.78 miles north 1.24 miles west then 1.20 miles south at the end of the tour what is Melinda's displacement vector
Answer:
The displacement vector is [tex]-0.59 \hat i -0.82 \hat j[/tex]
Explanation:
Taking East as positive x-axis having a unit vector [tex]\hat i[/tex] and North as positive y-axis having a unit vector [tex]\hat j[/tex].
So, west and south are in negative x and negative y directions respectively.
As she walks 0.40 miles south, 0.65 miles east, 0.78 miles north, 1.24 miles west then 1.20 miles south.
Scaling 1 mile as 1 unit vector, so 1 mile east = 1 [tex]\hat i[/tex] and so on
Adding all the displacement vectors, we have
[tex]\vec {v} = -0.40 \hat j +0.65 \hat i + 0.78 \hat j -1.24 \hat i - 1.20 \hat j[/tex]
[tex]\vec {v} = -0.59 \hat i -0.82 \hat j[/tex]
Hence, the displacement vector is [tex]-0.59 \hat i -0.82 \hat j[/tex]
a ball bounce on the ground. at what position (A,B,C)does the ball have the greatest potential energy? kinetic energy? explain your answer.
Answer:
What is the meaning of the kinetic I think the answer is both the ball has both Kinetic and potential energy so I think is the answer is true
9. A student notices that wearing darker colors in sunlight makes him feel warmer, so he decides to conduct an experiment. He takes five pieces of different
colored cloth and wraps
each one around a water bottle. He then places all five bottles in direct sunlight and measures the temperature of the water in each bottle an hour later
What is the dependent variable in this experiment?
O the time he leaves it in the sunlight
O the amount of water in each bottle
O the color of the cloth
O the temperature of the water
Answer: 4
Explanation:
The dependent variable is the temperature of the water.
When an object moves, where does the energy come from?
Answer:
Kinetic energy.
Explanation:
This is the energy of motion, observable as the movement of an object or subatomic particle. Every moving object and particle have kinetic energy.
The law of __________________________ says that people think of similar objects as belonging together.
Answer:
Explanation:is the law means that the police are the law
A force of 900N acts on
a stationary body
for 40sec and the body acquires the velocity of360 m/s calculate mass a body.
Answer:
Explanation:
It is still using F = m*a -- just in a disguised form.
Givens
F = 900 N
vf = 360 m/s
vi = 0
t = 40 second
Formulas
a = (vf - vi)//t
F = m * a
Solution
a = (360 - 0)/ 40
a = 9
F = m * a
900 = m * 9
m = 900/9
m - 100 kg. Doesn't seem high enough.
Answer:
a= V- u/t
a= 360 - 0 /40 = 9 m/sec2
F = MA
900 = M * 9
M = 900/9
M= 100 kg
a 10 kilogram steel ball is dropped from the top of a tower 100 meters high the kinetic energy of the ball just before it sttikes the ground is most nearly
Explanation:
If we assume negligible air resistance and heat loss, we can assume that all of the Gravitational potential energy of the ball will turn into Kinetic energy as it falls toward the ground.
Therefore our Kinetic energy = mgh = (10kg)(9.81N/kg)(100m) = 9,810J.
a beaker weighs 0.4N when empty and1.4N when filled with water what does ot weigh when filled with brine of density 1.2 g/cm3
Answer:2.47
Explanation:
So, the beaker weighs 1.40N when filled with water, brine of density weighs about 1.7N, you add the density + water. Have a good day!
29. A student notices that wearing care colors insight makes him feel warmer se he decides to conduct an experiment. He kese seces of bored and was
each one around a bete beten places alive betties in direct sunlight and measures the temperature of the water in each clean hout
what is the independent variable in this exermet
the temperature of the water
the outside temperature
the color of the con
Answer:
This question is unclear but the answer is:
the color of the con
Explanation:
In an experiment, the independent variable is the variable that is changed or manipulated by the experimenter to achieve a measurable response.
In this experiment which involves a student that notices that wearing care colors insight makes him feel warmer se. He decides to conduct an experiment by manipulating the colors of the cares, hence, the color of the con is the independent variable.
What is the net force of the diagram?
A racecar is driving around a circular track. The car is moving with a speed of 49.7 m/s, and the track has a radius of 114 m. What is the magnitude of the centripetal acceleration of the car?
Answer:
21.67 m/s²
Explanation:
From the question given above, the following data were obtained:
Velocity (v) = 49.7 m/s
Radius (r) = 114 m
Centripetal acceleration (a) =?
The centripetal acceleration can be obtained by using the following formula:
a = v²/r
a = 49.7² / 114
a = 2470.09 / 114
a = 21.67 m/s²
Therefore, the centripetal acceleration of the car is 21.67 m/s²