Question

a body of weight 450 Newtons is pushed by a force of 100 Newton on a rough horizontal plane if the line of action of push is 25° with the horizontal find the coefficient of friction

Answer 1

Explanation:

Given that,

Weight, W=100N

Acceleration, a=1m/s

2

Acceleration when force is double, a=10m/s

2

Now, Let the External Force be F and friction force be f.

Then,

F−f

s

=ma

F−μN=ma

F−μ100=10×1

F−μ100=10....(I)

We know, When Force is doubled,

Then,

2F−f

s

=ma

2F−μN=ma

2F−μ100=10×10

2F−μ100=100....(II)

Now, from equation (I) and (II)

F=90N

Now, put the value of F in equation (I)

90−μ100=10

−μ100=10−90

μ=

100

80

μ=0.8

Hence, the coefficient of restitution is 0.8