Explanation :
When a person is sliding with constant velocity, the forces that are acting on him are :
(1) Weight, W = mg where g is acceleration due to gravity.
(2) Friction forces acting opposite to the direction of motion.
(3) Normal force.
The forces acting on the person is balanced because the person is sliding with constant velocity.
From figure it is clear that, friction force is balanced by [tex]w\ sin\theta[/tex] and normal is balanced by [tex]w\ cos\theta[/tex].
Answer:
It is D.
Explanation:
Gravity and friction are acting on the person. The forces are balanced. There is no net force because the person is moving at a constant velocity. In this example, there is no net force when a mass moves at constant velocity. Although friction is acting on the person, there is no change in velocity and friction is not a net force in this case. Friction is only a net force if it changes the velocity of a mass. If friction slowed the person down, then there is a net force.
