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Tamiku [17]
3 years ago
14

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

. -900 kg-m/s2 C. -1,080 kg-m/s D. -1,800 N
Physics
1 answer:
Zielflug [23.3K]3 years ago
5 0

Answer:

B. -900 kg-m/s2

Explanation:

First of all, we need to calculate the acceleration of the hockey player, which is given by:

a=\frac{v-u}{t}

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

a=\frac{12 m/s-18 m/s}{0.6 s}=-10 m/s^2

And now we can calculate the force exerted by using Newton's second law:

F=ma

where m=90 kg is the mass of the hockey player. Substituting into the formula, we find

F=(90 kg)(-10 m/s^2)=-900 N

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