Understanding Free Body Diagrams

What does a free body diagram represent?

• The forces acting on an object

• The speed of an object

• The color of an object

• The temperature of an object

When a book is at rest on a table, what can be said about the forces acting on it?

• The forces are only upward

• The forces are unbalanced

• There are no forces acting

• The forces are balanced

If a book is moving across a rough surface and speeding up, what can be inferred about the forces?

• The forces are unbalanced

• There is no friction

• The forces are balanced

• The applied force is less than friction

What role does friction play when a book is moving at a constant velocity across a surface?

• It has no effect

• It only acts upwards

• It balances the applied force

• It speeds up the book

What happens to the forces when a book comes to a stop on a rough surface?

• The forces are balanced

• The forces are unbalanced

• There is no friction

• The applied force is greater than friction

On a frictionless surface, what is true about the forces acting on a box being pushed?

• The box cannot move

• There is friction opposing the motion

• The forces are balanced

• There is only an applied force

What is the state of forces when a hockey puck slides at constant velocity?

• There is no gravitational force

• The forces are balanced

• The forces are unbalanced

• There is a force pushing it forward

When a girl is hanging motionless from a bar, what can be said about the forces?

• The forces are unbalanced

• The forces are balanced

• There is no tension

• The gravitational force is zero

If an egg is free falling with increasing velocity, what is true about air resistance?

• There is no air resistance

• Air resistance is less than gravity

• Air resistance is equal to gravity

• Air resistance is greater than gravity

What must be true for an elevator moving upward and speeding up?

• The tension force is greater than gravity

• The forces are balanced

• There is no gravitational force

• The tension force is less than gravity