If a 90 kg hockey player slows from 18 m/s to 12 m/s over 0.6 s, what is the force exerted by his skates on the ice? A. -540 N B
1 answer:
Answer:
B. -900 kg-m/s2
Explanation:
First of all, we need to calculate the acceleration of the hockey player, which is given by:
where
v = 12 m/s is the final speed
u = 18 m/s is the initial speed
t = 0.6 s is the time
Substituting into the formula, we find
And now we can calculate the force exerted by using Newton's second law:
where m=90 kg is the mass of the hockey player. Substituting into the formula, we find
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Answer:
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Explanation:
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