Friction Newton's Second Law of Motion

[maxon1017]

Science howework

A crate rests on a horiontal floor. Only gravity and the support force of the floor act on it. A slight pull P is exerted on the crate, not enough to move it. A force of friction f now acts on it.

is f, less than, equal, or greater than P?

is the net force on the crate zero or greater than zero?

P is increased until the crate begins to move. it is pulled at a constant velocity across the floor.

f is: less than, equal to or greater than P?

is the net force on the crate zero, less than or greater than zero?

P is further increased and is now greater than friction f.

is the net force on the crate zero, less than or greater than zero?

 

[Deeviant]

Science howework

A crate rests on a horiontal floor. Only gravity and the support force of the floor act on it. A slight pull P is exerted on the crate, not enough to move it. A force of friction f now acts on it.

is f, less than, equal, or greater than P?

is the net force on the crate zero or greater than zero?

P is increased until the crate begins to move. it is pulled at a constant velocity across the floor.

f is: less than, equal to or greater than P?

is the net force on the crate zero, less than or greater than zero?

P is further increased and is now greater than friction f.

is the net force on the crate zero, less than or greater than zero?

First of all, there is a homework help area of these forums, yet, even there people like to help flesh out your knowledge of the theory behind the questions allowing you to find the answer yourself rather then to answer the questions themselfs.

But to help you out, let me ask you a few questions..

If something is not accelerating, would that be a good indication that the net force acting on it would be zero?(yes)

If the net force is zero, and there is a force applied to the crate, what do you think the force of friction would have to be to counteract it?

If you can understand my first two questions, you can answer all four of the questions in your homework.