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

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

its c i just checked it

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