A hockey player skates across a rink of length 75 m in 8.9 seconds.

a. What is the average speed of the hockey player?

b. It takes the hockey player 6 seconds to increase his speed from 3 m/s to 7.4 m/s. What is the acceleration of the hockey player?

c. The hockey player is moving at a speed of 9.5 m/s when eh starts to brake. He comes to a stop after traveling a distance of 4 m. What was his acceleration?

Respuesta :

a) v=d/t=75/8.9=8.43 m/s

b) a=(v2-v1)/6=(7.4-3)/6=0.73 m/s/s

c) [tex]a=\frac{v2^{2}-v1^{2} }{2d}=\frac{9.5^{2}-0^{2} }{2*4}=11.28[/tex] m/s/s