Impulse: Clay ball that sticks vs. Rubber ball that bounces?

AI Thread Summary
The discussion centers on comparing the impulse exerted by a rubber ball and a clay ball, both weighing 10 g, when thrown at a wall with equal speeds. The rubber ball bounces back, while the clay ball sticks to the wall, leading to a difference in impulse. The key point is that impulse can be calculated using the change in velocity (Δv), which is greater for the rubber ball as it changes direction, resulting in a Δv of approximately -2x. In contrast, the clay ball's change in velocity is only -x. Therefore, the rubber ball exerts a larger impulse on the wall due to its greater change in velocity.
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Homework Statement



A 10 g rubber ball and a 10 g clay ball are thrown at a
wall with equal speeds. The rubber ball bounces, the
clay ball sticks. Which ball exerts a larger impulse on
the wall?


Homework Equations



J (impulse) = Favg*dt


The Attempt at a Solution



I think that the rubber ball would exert more of an impulse because it's dt would be larger. Since it has to hit the ball and bounce of it, as opposed to the clay, which hits the wall and stops.

Thoughts?
 
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Impulse is either F*Δt or m*Δv.
The first expression is difficult to use because you don't actually know the force and duration of the collisions with the wall. Use the second expression. The difference is in the Δv.
 
Thought I replied to this.

Okay, so with the clay ball, the change in v is from x to 0, so it's -x. The rubber ball bounces though...and though it may leave the wall with a different speed, it's velocity has changed more than the clay ball's since it changed direction (x to -x...so -2x roughly). Therefore the rubber ball is exerts more impulse on the wall?
 
right.
 
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