Answer to Question #150207 in Physics for Andu

Question

The body with mass m = 3 kg, under the action of the attractive force F = 10 N, slides in the horizontal plane and traverses the mug 20 m during the time 4 s, starting from the resting state. Calculate the friction force of the flesh exerted by the ground on the body.

Answer 1

Find acceleration:

$$a=\sqrt{2d/t^2}.$$

Describe the motion according to Newton's second law:

$$ma=F-f,\\ f=F-ma=F-m\sqrt{2d/t^2}=5.3\text{ N}.$$