Question

Which of the following expressions are correct for impulse?A. mvB. F∆tC. FvD. ∆p

Answer 1

Answer:

impulse = F∆t

Explanation:

Answer 2

Answer:

B. F∆t

D. ∆p

Explanation:

Both formulas are correct. In fact, impulse is defined as the product between the force applied (F) and the time interval in which the force is applied (∆t

):

I = F∆t

So, option B. is correct. However, we see that this expression corresponds also to the change in momentum (option D)

in fact, we can rewrite the force as:

$I=(ma)\Delta t$

but the acceleration can be rewritten as ratio between change in velocity and change in time:

$I=m\frac{\Delta v}{\Delta t} \Delta t=m \Delta v = \Delta p$

which corresponds to the change in momentum.