Chapter 6 Physics Quiz
a ball with a momentum of 40kgm/s hits a wall and bounces straight back without losing any kinetic energy. What is the change in the ball's momentum
-8.0 kgm/s
Each croquet ball in a set has a mass of .50 kg. The green ball travels at 10.5 m/s and strikes a stationary red ball. If the green ball stops moving, what is the final speed of the red ball after the collision
10.5 m/s, because they switch velocities
a 2.0 kg baseball is pitched with a velocity of 40 m/s and is then batted to the pitcher with a velocity of 60 m/s. What is the magnitude of change in the ball's momentum
20 kgm/s
if a force is exerted on an object, which statement is true
a small force applied over a long time interval can produce a large change in the object's momentum
how can a small force produce a large change in momentum
a small force can produce a large change in momentum with a long contact time
Which of the following has the greatest momentum
a tortoise with a mass of 275 kg at a velocity of .55 m/s
a 75 kg person walking around a corner bumped into a 80 kg person who was running around the same corner. The momentum of the 80 kg person
decreased
two billiard balls collide. Identify the type of collision
elastic
describe the forces acting on a car as it moves along a level highway in still air at a constant speedd
force of gravity going down, normal force going up equal to the force of gravity, and the applied force in the direction the car is going in and opposite
a moderate force will break an egg. Using the concepts of momentum, force, and time interval, explain why an egg is more likely to break when it is dropped on concrete than if it is dropped on grass
grass will have a longer time interval because it has a softer cushion than concrete
a roller coaster climbs up a hill at 4 m/s and then zips down the hill at 30 m/s. The momentum of the roller coaster
is greater down the hill than up the hill
a billiard ball collides with a stationary identical billiard ball is an elastic head-on collision. After the collision, which of the following is true of the first ball
it comes to rest
describe how applying the brakes to stop a bicycle is an example of force
it is causing the object to change the acceleration
why is air resistance considered a form of friction
it is causing the object to slow down
why is the sound produced by a collision evidence that the collision is not perfectly elastic
it shows that energy isn't conserved and is elastic energy in conserved
the impulse experienced by a body is equivalent to the body's change in
momentum
in a two-body collision,
momentum is always conserved
which if the following statements about the conservation of momentum is not correct
momentum is not conserved for a system of objects in a head-on collision
which of the following best describes the momentum of two bodies after a two-body collision if the kinetic energy of the system is conserved
must also be conserved
is it possible for a spaceship traveling with constant velocity to experience a change in momentum? Explain your answer
no it cannot change because the mass will stay the same and velocity is constant
two balls of dough collide and stick together identify the type of collision
perfectly inelastic
two objects stick together and move with a common velocity after colliding. Identify the type of collision
perfectly inelastic
a child with a mass of 23 kg rides a bike with a mass of 5.5 kg at a velocity of 4.5 m/s to the south. Compare the momentum of the child with the momentum, of the bike
the child has a greater momentum, than the bike
a baseball pitcher's first pitch is a fastball, moving at high speed. The pitcher's second pitch - with the same ball - is a changeup, moving more slowly. Which pitch is harder for the catcher to stop? Explain your answer in terms of momentum
the fast ball because it has a greater momentum
two objects with different masses collide and bounce back after an elastic collision. Before the collision, the two objects were moving at velocities equal in magnitude but opposite direction. After the collision,
the less massive object had gained momentum
when comparing the momentum of two moving objects, which of the following is correct
the less massive object will have less momentum, if the velocities are the same
in an elastic collision between two objects with unequal masses,
the momentum of one object will increase by the amount that the momentum of the other object decreases
as a bullet travels through the air, it slows down due to air resistance. How does the bullets momentum change as a result
the momentum reduces because although the mass stays the same, the velocity slows down
two billiard balls of equal mass are traveling straight toward each other with the same speed. They meet head-on in an elastic collision. What is the total momentum of the system containing the two balls before the collision
the total momentum is zero because the masses and velocities are the same therefore they cancel out
the law of conservation of momentum states that
the total momentum of all objects interacting with one another remains constant regardless of the nature of the forces between the objects
two skaters stand facing each other. One skater's mass is 60 kg, and the other's mass is 72 kg. If the skaters push away from each other without spinning
their momenta are equal but opposite
two swimmers relax close together on air mattresses in a pool. One swimmer's mass is 48 kg, and the other's mass is 55 kg. If the swimmers push away from each other,
their momenta are equal but opposite
what is the natural tendency of an object that is in motion
to stay in motion unless acted upon by an outside force
when a car is moving, what happens to the velocity and acceleration of the car if the air resistance becomes equal to the force acting in the opposite direction
velocity is constant. a = o
a person sitting in a chair with wheels stands up, causing the chair to roll backward across the floor. The momentum of the chair
was zero while stationary and increased when the person stood
why is force not a scalar quantity
weight is needed in force, which is a vector
distinguish between mass and weight
weight is the force exerted by gravity, while mass is the actual amount of material of the object. Weight is also measured in N while mass is measured in kg
a student walks to class at a velocity of 3 m/s. To avoid walking into a door as it opens, the student slows to a velocity of .5 m/s. Now late for class, the student runs down the corridor at a velocity of 7 m/s. At what point in this scenario does the student have the least momentum
when the student slows to .5 m/s because that is when the velocity is the slowest
