What is the coefficient of friction if a block requires 20 N to slide across a surface with a normal force of 50 N?

To determine the coefficient of friction, you can use the formula for frictional force, which is expressed as:

Frictional force = Coefficient of friction × Normal force.

In this scenario, the block requires a force of 20 N to start sliding across the surface, and the normal force acting on the block is 50 N. By substituting these values into the formula, you can find the coefficient of friction:

20 N = Coefficient of friction × 50 N.

To isolate the coefficient of friction, divide both sides of the equation by the normal force (50 N):

Coefficient of friction = 20 N / 50 N.

Calculating this gives:

Coefficient of friction = 0.4.

This means that a coefficient of friction of 0.4 indicates that for every 50 N of force acting perpendicular to the surface, 20 N of force is required to overcome the friction and initiate movement. This value indicates a moderate level of friction between the surfaces involved.