Question

a body of mass m moves up through a distance x on an inclined plane at an angle q with hotizontal. the work done against friction is​

Answer 1

Answer:

The work done against friction is​ μmgcosqx.

Explanation:

Let the body of mass m be placed on an inclined plane and let it be displaced from A to B by a distance "x".And after breaking the component of the weight of the body we get;

• $mgsinq$ is the component down the inclined plane.
• $mgsinq$is the component perpendicular to the plane.

And the normal reaction (N) in the body is given as,

$N=mgcosq$        (1)

As the body is displaced up the inclined plane, the force of friction will be down the inclined plane i.e.

$f=\mu N$        (2)

Where,

f=force of friction

μ=coefficient of friction

N=normal reaction in the body

By substituting the value of f and N in equation (2) we get;

$f=\mu mgcosq$ (3)

And the work done(W) is given as,

$W=f.x$       (4)

By substituting the required values in equation (4) we get;

$W=\mu mgcosqx$

Hence, the work done against friction is​ μmgcosqx.