The crate is at rest on the incline. what can you say about the force of friction acting on the crate?

Explanation:

When a crate is placed on the inclined plane at rest then all the forces on the crate must be balanced

So we can say that force normal to the inclined plane is balanced due to component of the weight

so it is given as

here we know that

m = mass of the crate

= angle of inclination of the inclined plane

now along the inclined plane we will say

another component of the weight will be balanced by the friction force on the crate