A man is pulling a block with a mass of 6.2 kg across a horizontal surface and accelerates the block at a

rate of 0.50 m/s^2
. The coefficient of kinetic friction between the block and the surface is 0.24. What is
the magnitude of the force with which the man pulls?

1 answer

To find the magnitude of the force with which the man pulls, we need to consider the forces acting on the block.

The force of friction opposing the motion of the block can be calculated using the formula:

Frictional force = coefficient of kinetic friction * normal force

The normal force can be calculated using the formula:

Normal force = mass * acceleration due to gravity

In this case, the acceleration due to gravity is approximately 9.8 m/s^2.

Normal force = 6.2 kg * 9.8 m/s^2 = 60.76 N

Frictional force = 0.24 * 60.76 N = 14.53 N

To accelerate the block at a rate of 0.50 m/s^2, the man needs to overcome the force of friction and provide an additional force. This additional force can be calculated using Newton's second law:

Force = mass * acceleration

Force = 6.2 kg * 0.50 m/s^2 = 3.1 N

The magnitude of the force with which the man pulls is the sum of the force of friction and the additional force:

Magnitude of force = 14.53 N + 3.1 N = 17.63 N

Therefore, the magnitude of the force with which the man pulls is approximately 17.63 N.