a block rests on a horizontal surface. the normal force is 20N. the coefficient of static friction between the block and the surface is 0,40 and the coefficient of dynamic friction is 0,20
b) what will the magnitude of the frictional force be if a horizontal force of magnitude 5N is exerted on the block?
To find the magnitude of the frictional force, we need to identify whether the block is in a static or dynamic state.
If the force of 5N is applied and the block is not moving, it is in a static state. In this case, the magnitude of the frictional force is given by the equation:
frictional force (static) = coefficient of static friction * normal force
frictional force (static) = 0.40 * 20N = 8N
Therefore, if a horizontal force of magnitude 5N is exerted on the block while it is not moving, the magnitude of the frictional force will be 8N.