Question

If a block moving up an inclined plane at 30° with a velocity of 5 metre per second stop after 0.5 second then coefficient of frictional will be there by

Answer 1

a is total deceleration of body.
then apply 0- v= -at
=> v=a t.

Answer 2

Initial Velocity u = 5 m/s

Time Taken t = 0.5 s

Final Velocity = 0

v = u + at

0 = 5 + 0.5a

a = - 10m/s^2

This stopping force is due to the frictional force.

fr = umg cos θ

ma = umg cos θ

u = a/g cos

u = 10/10 cos 30

u = 2/√3

u = 1.15