If a hockey player starts from rest and accelerates at a rate of 2.1 m/s2, how long does it take him to skate 30 m?

U = 0
a = 2.1 m/s²
s = 30m
t = ?

s = ut + 1/2 at²
⇒ 30 = 0×t + 1/2 × 2.1 × t²
⇒ 30 = 1.05 t²
⇒ t² = 30/1.05 = 28.57
⇒ t = √28.57
⇒ t = 5.34 second

It will take 5.34 second

 

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