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A shot putter shoots a 7.3kg shot from rest to 14m/s in 1.5s. what was the average power?

User Abhinay
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1 Answer

6 votes

Answer: 477W

Step-by-step explanation:

Given the following :

Mass (m) = 7.3kg

Initial Velocity (u) = 0

Final velocity (v) = 14m/s

time (t) = 1.5s

Power = workdone (W) / time (t)

The workdone can be calculated as the change in kinetic energy (KE) :

Recall ;

KE = 0.5mv^2

Therefore, change in KE is given by:

0.5mv^2 - 0.5mu^2

Change in KE = 0.5(7.3)(14^2) - 0.5(7.3)(0^2)

Change in KE = 715.4J

Therefore ;

Average power = Workdone / time

Workdone = change in KE = 715.4N

Average power = 715.4 / 1.5

Average power = 476.93333 W

= 477W

User SuitUp
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