Question

Why When one end of a horizontal plane is lifted a certain stage(angle of response) is reached when an object resting on it begins to slide down the plane?

Answer 1

It begins to slide when mgsin(theta) i.e. force due to weight along the incline becomes greater than the force of friction.

Explanation:

Answer 2

Answer:

It begins to slide when mgsin(theta) i.e. force due to weight along the incline becomes greater than the force of friction.

Objects are known to accelerate down inclined planes because of an unbalanced force. ... The force of gravity (also known as weight) acts in a downward direction; yet the normal force acts in a direction perpendicular to the surface (in fact, normal means "perpendicular").