Question

In a lab environment, you are investigating the impulse of a force exerted on a brick when the brick's speed is reduced from 2.5 m/s to a complete stop. First, you allow the brick to slam into a secured piece of wood, bringing the brick to a sudden stop. Second, you allow the brick to plow into a large slab of gelatin so that the brick comes to a gradual halt. In which situation is there a greater impulse of the force on the brick?

Answer 1

Answer:

The impulse will be equal

Explanation:

Impulse is defined as the change in momentum.

$J=mv_2-mv_1\\\Rightarrow J=m(v_2-v_1)$

Where,

m = Mass of the brick

$v_2$ = Final velocity of the brick = 0

$v_1$ = Initial velocity of the brick = 2.5 m/s

So,

$J=m(v_2-v_1)\\\Rightarrow J=m(0-2.5)\\\Rightarrow J=-2.5m\ Ns$

As, it can be seen here the time taken is irrelevant when it comes to calculating impulse. In both cases of brick and gelatin the initial and final velocities are same hence, the impulse will be equal.