Question

A child is bouncing an a trampoline. The child has a mass of 50.5 kg . She leaves the surface of the trampoline with an initial upwards velocity of 10.2 m/s . When she reaches height 1.60 m above the trampoline (still on the way up), she grabs a large (stationary) plastic block. The mass of the block is 8.00 kg .

(Figure 1)

For this problem, use g=9.80 meters per second per second for the magnitude of the acceleration due to gravity.

Part A

What is the speed vbefore of the child immediately before she grabs the block?

Express your answer numerically in meters per second.

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Hint 1. How to approach the problem

Use conservation of energy. Find the initial kinetic energy Ki of the girl as she leaves the trampoline. Then find her gravitational potential energy Ubefore just before she grabs the block (define her initial potential energy to be zero). According to the principle of conservation of energy, Ki=Ubefore+Kbefore. Once you have Kbefore, use the definition of translational kinetic energy to find the girl's speed vbefore.

vbefore =

m/s

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Part B

What is the speed vafter of the girl immediately after she grabs the block?

Express your answer numerically in meters per second.

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vafter =

m/s

Submit

Part C

This question will be shown after you complete previous question(s).

Part D

What is the maximum height hmax that the girl (with block) reaches? Measure hmax with respect to the top of the trampoline.

Express your answer numerically in meters.

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hmax =

m

Answer 1