Question

Please solve this qs for me show all steps and clear explaining

At point A the wooden block below is traveling at 2.3 m/s. The coefficient of kinetic friction between the level table and the block is 0.22. The block slides and then falls off the table. How much work docs friction do between point A and point B (just before it hits the floor)? How much work is done by gravity between points A and B? Use the Work-Energy Theorem to determine the kinetic energy of the block at B.

Answer 1

a)

work done by frictionWf = fk*AB*cos180

fk = uk*m*g

AB = 0.8 m

Wf = -0.22*1.8*9.8*0.8 = -3.10464 J

(b)

work done by gravity Wg = m*g*h = 1.8*9.8*1.4 = 24.696 J

(c)

work energy theorem

total work done = change in KE

W = 0.5*m*(v^2-u^2)

24.696 - 3.10464 = 0.5*1.4*(v^2-2.3^2)

v = 6.01 m/s   <<<<<-----------answer