Free Body diagrams and problem solving AP Physics 1

Free Body Diagrams A pictorial representation of forces acting on an object complete with labels. Consider the box being pulled to the right by a rope across the floor FBD

TWO types of Friction

3 Common Forms of Friction

Sliding Friction Depends on Two Things: 1. 2.

Rolling Friction Fluid Friction Depends on Three Things: 1. 2. 3.

Example #1 How much does a 0.25 kg apple weigh? What is the mass of a 15 N toy car?

Example #2 A horizontal net force of 25 N acts on a 12 kg object. What is the acceleration of the object?

Example #3 A 10-kg box is being pulled across the table to the right at a constant speed with a force of 50N. Calculate the Force of Friction Calculate the Normal Force

Example #4 Suppose a 5kg box is being pulled by a 50 N force at an angle of 30o above the horizontal. The box accelerates horizontally at 1 m/s2. Calculate the Force of Friction Calculate the Normal Force

Example #5 A crane applies a force of 500N to a 25kg crate as it is raised into the air. What is the acceleration of the crate?

Example #6 What is the coefficient of kinetic friction between the crate and the floor? A 1500 N crate is being pushed across a level floor at a constant speed by a force F of 600 N at an angle of 20° below the horizontal. FBD