Question

Which notations are commonly used on force diagrams to show forces acting on an object? Check all that apply. Fp Fz FN Ff FD Fg

Answer 1

Fp, Fn, Ff, Fg. The only reason I know is because I highlighted it in my notes.

Answer 2

Answer:

Fp, Ff, Fg, FN

Explanation:

Consider an object which is pushed along a horizontal surface. There are four forces acting on the object:

- The force of gravity (Fg), which is the force due to the attraction between the Earth and the object. It can be calculated as Fg = mg, where m is the mass of the object and g is the acceleration due to gravity, and it is directed downward.

- The normal reaction (FN), which is the force that the surface exerts on the object in order to counter-balance the force of gravity, and it is directed upward. It is equal in magnitude to the force of gravity.

- The force of push (Fp), which is the force applied when pushing the object and make it sliding along the surface. It is directed horizontally.

- The force of friction (Ff), which is the force that opposes to the motion of the object, and its direction is opposite to Fp. It is due to the contact between the molecules at the edge of the object and the molecules of the surface. Its magnitude is equal to $F_f = \mu mg$ where $\mu$ is the coefficient of friction, m is the mass of the object and g the acceleration due to gravity.