Which of these objects has the greatest momentum?

A
A 1,250-kg car moving at 5 m/s

B
An 80-kg person running at 4 m/s

C
A 10-kg piece of meteorite moving at 600 m/s

D
A 0.5-kg rock moving at 40 m/s

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Question

Compare two objects: a loaded dump truck moving slowly and a small sports car moving at highway speed. Which one is harder to stop and why, using the concept of momentum?

Answer

The loaded dump truck is harder to stop. While the sports car may have a high velocity, the dump truck's significantly greater mass results in a larger momentum (p = m*v). A larger momentum requires a greater force or a longer time to bring to rest.

Question

A 0.06 kg tennis ball is served at 50 m/s. What is its momentum? How does this compare to the momentum of a 7 kg bowling ball rolling at 2 m/s?

Answer

Tennis ball momentum: 0.06 kg * 50 m/s = 3 kg·m/s. Bowling ball momentum: 7 kg * 2 m/s = 14 kg·m/s. The slower, heavier bowling ball has more than 4 times the momentum of the fast, light tennis ball.

Question

A hockey puck slides across frictionless ice at a constant velocity. Explain what happens to its momentum if its mass suddenly doubles (imagine it collects snow) while its velocity remains unchanged.

Answer

Its momentum doubles. Momentum is directly proportional to mass (p = m*v). If mass doubles and velocity is constant, the product (momentum) also doubles.

Question

What is the impulse required to stop a 5 kg object moving at 10 m/s? How is impulse related to momentum change?

Answer

The impulse required is -50 N·s (or 50 N·s in the direction opposing motion). Impulse is defined as the change in momentum. To stop the object, its final momentum must be 0. Change in momentum = 0 - (5 kg * 10 m/s) = -50 kg·m/s.

Question

In a closed system, two identical carts initially at rest are pushed apart by a spring. If one cart moves left at 3 m/s, what is the velocity of the other cart? (Assume equal mass).

Answer

3 m/s to the right. The initial total momentum of the system is zero. For momentum to remain conserved (final total momentum = 0), the momenta of the two carts must be equal in magnitude and opposite in direction. Since masses are equal, their velocities must be equal and opposite.

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Does an object with a large mass always have more momentum than an object with a small mass?

Which of these objects has the greatest momentum?

A
A 1,250-kg car moving at 5 m/s

B
An 80-kg person running at 4 m/s

C
A 10-kg piece of meteorite moving at 600 m/s

D
A 0.5-kg rock moving at 40 m/s

The object with the greatest momentum is a 1,250-kg car moving at 5 m/s.

Topic Flashcards

Mini Quiz

Related Questions

Which of these objects has the greatest momentum?

A A 1,250-kg car moving at 5 m/s B An 80-kg person running at 4 m/s C A 10-kg piece of meteorite moving at 600 m/s D A 0.5-kg rock moving at 40 m/s

The object with the greatest momentum is a 1,250-kg car moving at 5 m/s.

Topic Flashcards

Mini Quiz

Related Questions

A
A 1,250-kg car moving at 5 m/s

B
An 80-kg person running at 4 m/s

C
A 10-kg piece of meteorite moving at 600 m/s

D
A 0.5-kg rock moving at 40 m/s