When a bar with a mass of 500 g moved over the surface, the coefficient of friction was 0.3, which is equal to the friction force.

Given:

m = 500 grams = 0.5 kilograms – body weight;

g = 9.8 Newton / kilogram – acceleration of gravity;

k = 0.3 – coefficient of friction.

It is required to determine F friction (Newton) – the friction force acting on the body.

To determine the friction force, you must use the following formula:

F friction = k * N, where N is the support reaction force, in this case equal to the body weight;

F friction = k * m * g = 0.3 * 0.5 * 9.8 = 0.15 * 9.8 = 1.47 Newton.

Answer: the body is affected by a friction force equal to 1.47 Newton.