# Problem: A boy of mass 64.7 kg is rescued from a hotel fire by leaping into a firefighters' net. The window from which he leaped was 8.9 m above the net. The firefighters lower their arms as he lands in the net so that he is brought to a complete stop in a time of 0.40 s. Ignore air resistance.What is the impulse on the net due to the boy during the interval (magnitude and direction)?

###### FREE Expert Solution

We'll use the kinematic equation:

$\overline{){{{\mathbf{v}}}_{{\mathbf{f}}}}^{{\mathbf{2}}}{\mathbf{=}}{{\mathbf{v}}_{\mathbf{0}}}^{{\mathbf{2}}}{\mathbf{+}}{\mathbf{2}}{\mathbit{a}}{\mathbit{s}}}$

In this problem:

The initial velocity, v0 = 0

Impulse = change in momentum.

99% (418 ratings) ###### Problem Details
A boy of mass 64.7 kg is rescued from a hotel fire by leaping into a firefighters' net. The window from which he leaped was 8.9 m above the net. The firefighters lower their arms as he lands in the net so that he is brought to a complete stop in a time of 0.40 s. Ignore air resistance.

What is the impulse on the net due to the boy during the interval (magnitude and direction)?

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What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Intro to Impulse concept. You can view video lessons to learn Intro to Impulse. Or if you need more Intro to Impulse practice, you can also practice Intro to Impulse practice problems.