- A book is at rest on a table top. The forces acting on the book are gravity (Fg) pulling downward and the normal force (Fn) from the table pushing upward. These two forces are equal in magnitude and opposite in direction, resulting in no net force and the book remaining at rest.
- A girl is suspended motionless from the ceiling by a rope. The forces acting on the girl are gravity (Fg) pulling downward and tension (T) in the rope pulling upward. These two forces are equal in magnitude and opposite in direction, resulting in no net force and the girl remaining motionless.
- An egg is free-falling from a nest in a tree. Neglecting air resistance, the only force acting on the egg is gravity (Fg) pulling downward. With no other forces present, the egg accelerates downward at the rate of gravitational acceleration.
- An egg is falling (not freely, do not neglect air resistance) from a nest in a tree. The forces acting on the egg are gravity (Fg) pulling downward and air resistance (Fa) pushing upward. Gravity is greater than air resistance, so the egg accelerates downward, but at a rate less than gravitational acceleration due to the opposing force of air resistance.
Parent Tip: Review the logic above to help your child master the concept of physics free body diagram worksheet.
