momentum test
1-N apple falls to the ground. The apple hits the ground with an impact force of
1 N
A piece of putty moving with 2 units of momentum strikes and sticks to a heavy bowling ball that is initially at rest. After the putty sticks to the ball, both are set in motion with a combined momentum that is
2 units
A ball is moving at 6.0 m/s and has a momentum of 24.0 kg·m/s. What is the ball's mass?
4.0 kg
A 4.0-kg ball has a momentum of 20.0 kg·m/s. What is the ball's speed?
5.0 m/s
A 5.0-kg chunk of putty moving at 10.0 m/s collides with and sticks to a 7.0-kg bowling ball that is initially at rest. The bowling ball with its putty passenger will then be set in motion with a momentum of
50.0 kg·m/s
A 2-kg ball is thrown at 3 m/s. What is the ball's momentum?
6 kg·m/s
Which of the following has the largest momentum?
A pickup truck traveling down the highway
A piece of putty and a rubber ball have the same mass. If you drop them from the same height, which object will produce a greater impulse and why?
The rubber ball will produce a greater impulse because it will bounce.
A truck travels north with a momentum of 2,600 kg·km/s, and a motorcycle heads west with a momentum of 1,500 kg·km/s. The motorcycle hits the truck. If the two vehicles collide and then stick together, what is the momentum and direction of travel?
The vehicles travel with a momentum of 3,000 kg·km/s in the NW direction.
When you jump off a step, you usually bend your knees as you reach the ground. By doing this, the time of the impact is about 10 times more what it would be in a stiff-legged landing, and the average force on your body is reduced by
about 10 times
A car traveling along the highway needs a certain amount of force exerted on it to stop. More stopping force may be required when the car has
all of the above
A collision is considered elastic if
all of the above
A karate expert executes a swift blow and splits a cement block with her bare hand.
all of the above
If the momentum of an object changes and its mass remains constant,
all of the above
In order to increase the final momentum of a golf ball, we could
all of the above
The force of an apple hitting the ground depends upon
all of the above
A cannon recoils from launching a cannonball. The speed of the cannon's recoil is small because the
cannon has far more mass than the cannonball
A freight train rolls along a track with considerable momentum. If it were to roll at the same speed but had twice as much mass, its momentum would be
doubled
If all people, animals, trains and trucks all over the world began to walk or run towards the east, then
earth would spin a bit slower
If the net external force acting on a system is zero, then the total momentum of the system is zero.
false
Impulses are normally smaller when bouncing takes place.
false
Momentum is NOT conserved when interacting objects don't move along the same straight line.
false
Momentum is a scalar quantity.
false
While roller-skating, Granny collides with her tiny grandson Ambrose who is at rest. Ignoring any friction effects, Ambrose's speed after the collision will be greatest when
he and Granny make a bouncing collision, each going in opposite directions.
A cannon fires a cannonball. The speed of the cannonball will be the same as the speed of the recoiling cannon
if the mass of the cannonball equals the mass of the cannon.
A cannon ball shot from a long-barrel cannon travels faster than one shot from a short-barrel cannon because the cannonball receives a greater
impulse
The momentum change of an object is equal to the
impulse acting on it
The reason padded dashboards are used in cars is that they
increase the time of impact in a collision.
A small economy car (low mass) and a limousine (high mass) are pushed from rest across a parking lot, equal distances with equal forces. The car that receives the greater impulse is the
limousine
The momentum of an object is defined as the object's
mass times its velocity
Two objects, A and B, have the same size and shape, but A is twice as heavy as B. When they are dropped simultaneously from a tower, they reach the ground at the same time, but A has a higher
momentum
A table tennis ball moving forward with 5 units of momentum strikes and bounces backward off a heavy bowling ball that is initially at rest and free to move. The bowling ball is set in motion with a momentum of
more than 5 units
A moving freight car runs into an identical car at rest on the track. The cars couple together. Compared to the velocity of the first car before the collision, the velocity of the combined cars after the collision is
one half as large
A meteor that originally was heading south breaks up into two chunks. One of the chunks moves southwest. The second chunk was not immediately found, but scientists guessed that they should look for an object heading
southeast
Superman is at rest in space when he throws an asteroid that has more mass than he does. Which moves faster, Superman or the asteroid?
superman
Suppose an astronaut in outer space wishes to toss a ball against a very massive and perfectly elastic concrete wall and catch it as it bounces back. If the ball is as massive as the astronaut, then
the astronaut will never catch the first bounce.
The force that accelerates a rocket into outer space is exerted on the rocket by
the exhaust gases
Which has more momentum, a large truck moving at 30 miles per hour or a small truck moving at 30 miles per hour?
the large truck
A table tennis ball launcher is fired. Compared to the force on the ball, the force on the launcher is
the same
A table tennis ball launcher is fired. Compared to the impulse on the ball, the impulse on the launcher is
the same
Suppose a cannon is made of a strong but very light material. Suppose also that the cannonball is more massive than the cannon itself. For such a system
the target would be a safer place than where the operator is located.
In order to catch a ball, a baseball player moves his or her hand backward in the direction of the ball's motion. Doing this reduces the force of impact on the player's hand principally because
the time of impact is increased.
Momentum of a system is conserved only when
there is no net external force acting on the system
Suppose a girl is standing on a pond where there is no friction between her feet and the ice. In order to get off the ice, she can
throw something in the direction opposite to the way she wants to go.
Automobile dashboards that are padded lengthen the time of impact in case of a collision.
true
If a net force acts on a system, the system's momentum will change.
true
Impulse is defined as the force exerted on an object times the time it lasts.
true
Momentum is defined as an object's mass times its velocity.
true
Perfectly elastic collisions between large objects are uncommon in the everyday world
true
When a baseball player follows through in hitting the ball, the contact time with the ball is longer
true
When two objects collide and completely bounce apart with no lasting deformation or generation of heat, the collision is said to be elastic.
true
When two objects collide and stick together, the collision is said to be inelastic
true
Compared to a sports car moving at 30 miles per hour, the same sports car moving at miles per hour has
twice as much the momentum
Recoil is noticeable if you throw a heavy ball while standing on roller skates. If instead you go through the motions of throwing the ball but hold onto it, your net recoil velocity will be
zero
Two gliders having the same mass and speed move toward each other on an air track and stick together. After the collision, the velocity of the gliders is
zero