Match each word to the sentence where it best fits.
- A/an _______ can be thought of as either the product of force and duration time or as change in momentum.
- An object’s _____ is a product of its mass and velocity.
|law of conservation of energy|| ||law of conservation of momentum|
- The _______ explains how it is possible for a rocket to speed up in empty space even if no external force is exerted on it.
|collision|| ||elastic collision|
|inelastic collision|| |
- A/An _______ is an interaction between objects that causes one or more of them to change velocity.
- Momentum is conserved in all collisions, but kinetic energy is only conserved in a/an _______.
- A collision where the objects stick together after impact is called a/an _______.
- Describe two different scenarios where the same object has identical momentum.
- A rubber ball and a clay ball of equal mass are dropped from the same height. The rubber ball bounces back up, and the clay ball sticks to the floor.
- Which ball has the greatest momentum just before hitting the floor, or are they equal?
- Which ball experiences a greater change in momentum as a result of the collision, or are they equal?
- Which ball experiences a greater change in kinetic energy as a result of the collision, or are they equal?
- For a given running speed, does it take more force to slow down if you are wearing a backpack or not?
- Philip is chasing his dog. He has four times more mass than the dog, but he can only run half as fast as the dog. What is Philip’s momentum, compared to his dog’s?
- Which sentence below best expresses the meaning of the following equation?
- Force multiplied by time equals momentum.
- The net force on an object multiplied by the change in momentum equals the impulse.
- The force on an object divided by the momentum is equal to the time duration.
- The change in momentum equals the net force exerted on the object multiplied by the time interval.
- Describe two situations in which it is possible to double the mass of an object without changing the momentum of the object.
- A stunt man jumps from a burning building and comes to rest at ground level. Consider his impulse during landing if he lands on a soft mat, on a concrete surface, or in a safety net. Which of the following is true?
- His impulse is greatest if he lands on a soft mat.
- His impulse is greatest if he lands on a concrete surface.
- His impulse is greatest if he lands in a safety net.
- The impulse is the same in all three cases.
- There is zero impulse in all three cases because he comes to rest.
- Stuart pushes a table with a force of 100 N. Is the impulse different if he pushes for 1 s or 10 s?
- If you want to increase an object’s momentum by the greatest amount possible, should you double the mass or the velocity while keeping the other the same?
- Are you better off in an accident where the hood is deformed or where the car is not damaged at all but bounces backward?
- When designing an egg drop container as on page 617, what are the comparative advantages of using a roll of white craft paper, as opposed to sheets of newspaper or bathroom tissue?
- Is impulse a vector quantity?
- Newton’s first law states that an object tends to stay in motion unless acted on by an external force. But braking—an internal force—causes a car to stop. Explain this apparent paradox.