Energy, Work & Power (6 of 31) Gravitational Potential Energy, Work Done By an External Force

TL;DR

External force work equals change in gravitational potential energy, showing the relationship between the two.

Transcript

okay in today's video I'm going to go over the relationship between potential energy and work in specific we're going to be talking about gravitational potential energy and work than before we talk about gravitational potential energy and work I just want to remind you that earlier we talked about kinetic energy and work and we had this thing we ca... Read More

Key Insights

• 💦 External force work is equal to the change in gravitational potential energy.
• 🏋️ The applied force when lifting objects equals the gravitational force (weight).
• 💦 Distance in the work equation represents the distance over which the external force is applied.
• 💦 The angle between displacement and applied force vectors is zero in external force work.
• 💦 The relationship between external force work and gravitational potential energy change is crucial in physics.
• 💦 Work energy principle applies to gravitational potential energy and external force work.
• 💦 Understanding the work equation and its relation to gravitational potential energy is essential.

Questions & Answers

Q: What is the relationship between external force work and gravitational potential energy change?

The work done by an external force is equal to the change in gravitational potential energy, showing a direct relationship between the two.

Q: How is the applied force related to the gravitational force when lifting objects?

When lifting an object at a constant velocity, the applied force is equal to the gravitational force (weight), which can be calculated as mass times acceleration due to gravity.

Q: What factors determine the distance in the work equation for lifting objects?

The distance in the work equation is the distance over which the external force is applied, commonly denoted as Delta Y or Delta H, representing the change in height of the object.

Q: Why is the angle between the displacement vector and applied force zero in the context of external force work?

When lifting an object with an external force, the angle between the displacement and applied force vectors is zero degrees as they are parallel and in the same direction, resulting in a cosine of zero degrees which is one.

Summary & Key Takeaways

• External force work equals change in gravitational potential energy.

• Applied force when lifting objects is equal to gravitational force (weight).

• Work done by an external force equals change in gravitational potential energy.