Work Energy proof part 4

The video tutorial explains the work-energy formula for particles, focusing on kinetic, gravitational, and elastic energy changes. It generalizes the formula to include multiple forces and provides an example using an inclined path. The tutorial highlights the conservation of mechanical energy and concludes with a suggestion for further reading on conservative and non-conservative forces.

What are the three forces acting on the particle in the work-energy formula?

• A spring force, friction, and a mysterious force

• Gravity, a normal force, and a mysterious force

• Gravity, friction, and a mysterious force

• Gravity, a spring force, and a mysterious force

How is the change in kinetic energy expressed in the work-energy formula?

• 1/2 times mass times change in velocity squared

• 1/2 times mass times velocity squared

• 1/2 times spring constant times displacement squared

• Mass times gravity times height

What does the work done by the third force represent in the generalized formula?

• The work done by friction only

• The work done by the spring force only

• The work done by gravity only

• The work done by all external forces

Why does the normal force on an inclined plane not perform work?

• It is equal to the gravitational force

• It is parallel to the direction of motion

• It is perpendicular to the direction of motion

• It is equal to the spring force

What is the sum of kinetic energy and potential energies called?

• Gravitational energy

• Total energy

• Elastic energy

• Mechanical energy

What happens to mechanical energy when no external work is done?

• It remains constant

• It is lost as heat

• It decreases

• It increases

Which of the following is a non-conservative force?

• Gravity

• Spring force

• Magnetic force

• Friction