Velocity and Acceleration
An object in a free fall accelerates at _______. (Include units)
9.8 m/s2
A 20 kg block is accelerated at 2 m/s2. The net force on the block is ______.
40 N
Bumper cars collide. This is an example of _______ collision.
Elastic Collision
Extra 100 if you can name an example of an inelastic collision.
Kepler’s first law states that each planet orbits the sun in a path called a(n)
Ellipse
A 100 kg cart is pushed to the top of a 15 m hill. How much gravitational PE does it now have?
14,700 J
A ball is thrown upward. At the top of the arc, the velocity of the ball is ________.
What is the mass of a car that is being accelerated to 1.5m/s2 by a 22,500 N force?
15,000 kg
A person jumping off of a 4 m high roof will bend their knees when landing on the ground. The reason for this is to ____________.
Increase the time of impact and decrease the force on their legs.
The diagram below represents the motion of a planet around the Sun, S.
(Ms. Villa will draw it)
When is the planet moving fastest?
When it's perihelion (close to the sun)
A 1200 kg car traveling at 35 m/s, has how much kinetic energy?
735000 J
A cart starting from rest travels a distance of 3.6 meters in 1.8 seconds. The average speed of the cart is
2 m/s
A 100 kg block of stone is being pushed by a 50 N force at a constant velocity. The frictional force is ____.
50 N
What is the mass of a car that has a momentum of 15,000 kg m/s and is moving with a velocity of 10 m/s?
1500 kg
A rock whirled on the end of a string moves in a circle because
The string continues to pull the rock inward even though the rock's inertia is pulling it outwards.
If you push a block with a force of 50 N for 10 meters, how much work did you do?
500 J
A car is traveling at 30 m/s. It then accelerates at a rate of 4 m/s2 for 4 seconds. The car’s velocity is now _____.
46 m/s
A 12.0 kg box is being pulled along level ground at constant velocity by a horizontal force. What is friction between the box and the floor if its coefficient of friction is 0.32?
38N
Extra 100 if you can explain the difference between having a coefficient of friction of 0.99 and 0.01.
A tennis ball leaves the racket on a serve with a speed of 55m/s. The mass of the ball is 0.06kg and is in contact with the racket for 0.004s. Determine the average force on the ball.
825 N
A 26kg block is placed on a turn table with a radius of 5m. What is the centripetal force on the block if the velocity is 7m/s?
254.6 N
A rock falls off a 100 m cliff. If the rock had 8000 J of PE at the top of the cliff, how much does it have KE does it have at the bottom of the cliff?
8000 J of KE ideally
Extra 100 if you can explain why "Ideally"
A ball is dropped from the top of a 73m tall building. How long will it take to hit the ground?
3.9 s
Find the Fnet on X and on Y if a desk is being pushed 30 N to the right but 20 N of frictional force was being pushed to the left.
On X: 10 N to the right
On Y: Equilibrium, 0N Extra 100 points if you can explain why Y is in equilibrium.
A 3221kg car traveling at 23 m/s collides with another 2350kg car that is at rest. The two bumpers lock and the cars move forward together. What is their final velocity?
13.3 m/s
The planet Jupiter has a mass of 5.9 x 1027 kg. A student of mass 55 kg is orbiting the planet a distance of 7.2 x 107 m away from the planet. What is the gravitational force of attraction between the two? (G= 6.67x10-11 Nm2/kg2)
4,175.2 N
A ball with mass of 3kg is dropped from the top of a building this is 20m high. What is the approximate velocity of the ball when it is just about to hit the ground?
19.8 m/s