A construction truck collides with the back of a subcompact car. Which vehicle has the larger ch
ange in momentum during the collision?

The small car has a larger change in its momentum.

The huge truck has a larger change in its momentum.

They have the same change in momentum.

Neither one changes its momentum.

Question

A construction truck collides with the back of a subcompact car. Which vehicle has the larger ch
ange in momentum during the collision?

The small car has a larger change in its momentum.

The huge truck has a larger change in its momentum.

They have the same change in momentum.

Neither one changes its momentum.

anonymous · Answer

The huge truck.
Two objects of different mass are moving at the same speed; the more massive object will have the greatest momentum.
A less massive object can never have more momentum than a more massive object.

anonymous · Answer

chiki22. What is we have a mass of x with a velocity 2v, and a mass of 2x and a velocity of x? These will have the same momentum, because $ p = mv$

JazzyCaz. This answer has several answers depending on what type of collision occurs (elastic or inelastic) and the initial conditions of the car and truck. Let's take a look at the math here. We know that momentum is always conserved regardless of which type of collision occurs. Therefore, $$p_{t,i} + p_{c,i} = p_{t,f} + p_{c,f}$$

turingtest · Answer

@ eashmore
What makes you think that the velocity and masses of the respective objects have those proportions? Both are unspecified. Did you just invent them hypothetically?
You are certainly right about the elastic/inelastic collision making a difference in something, but it is in conservation of kinetic energy only.
Momentum is always conserved as you said, so the only answer is$$p_{ti} + p_{ci} = p_{tf} + p_{cf}\to p_{ti}-p_{tf}=p_{ci}-p_{cf}\to \Delta p_t=\Delta p_c$$

turingtest · Answer

@eashmore
I'm pretty sure you knew that, but your answer confused me a bit, so I wanted to clarify for the asker.

anonymous · Answer

I gave those proportions as a counter-point to chiki22's statement that "a less massive object can never have more momentum than a more massive object."

In regards to the type of collision, I was trying to be thorough. Then present the idea that using conservation of momentum eliminates this discrepancy.

turingtest · Answer

ok, I figured you had a reasonable explanation.
The first time I read your answer I thought it said you knew the proportions to be such. After re-reading I saw that you probably meant what you just said. Hence I gave you the medal.