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?a. The impulse is the same in both situations.b. There is a greater impulse of the force on the brick from the gelatin.c. Not enough information is given to determine the answer.d. There is a greater impulse of the force on the brick from the wall.

Answer 1

a) The impulse is the same in both situations

Step-by-step explanation:

Impulse = Change in momentum

Impulse = m(v₂ - v₁)

The speed was brought to a stop in both cases, it doesn't matter whether it is suddenly or slowly, v₂ = 0 m/s for both cases. The initial speed is also v₁ = 2.5 m/s for both cases. Since v₂ and v₁ is the same for both cases, v₂-v₁ is also the same, hence change in momentum is the same since the mass remains unchanged.

Since impulse is concerned with change in momentum, i.e. Final momentum - initial momentum, the impulse is the same in both situations.