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irga5000 [103]
3 years ago
14

Paul lifts a sack weighing 245 newtons vertically from the ground and places it on a platform at a height of 0.7 meters. If he t

akes 10 seconds to do this task, what power has he expended during this time? A. 10 watts B. 17.15 watts C. 23.6 watts D. 29.8 watts
Physics
1 answer:
d1i1m1o1n [39]3 years ago
6 0

Answer:

B. 17.15 watts

Explanation:

Given that

Time = 10 seconds

height = distance = 0.7 meters

weight of sack = mg = F = 245 newtons

Power = work done/ time taken

Where work done = force × distance

Substituting the given parameters into the formula

Work done = 245 newton × 0.7 meters

Work done = 171.5 J

Recall,

Power = work done/time

Power = 171.5 J ÷ 10

Power = 17.15 watts

Hence the power expended is B. 17.15 watts

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