Work, Energy, & Power - Formulas and Equations - College Physics

TL;DR

Learn about the equations and formulas for calculating work, energy, and power in various scenarios.

Transcript

in this video we're going to go over the equations and formulas that's associated with work energy and power so let's say we have a block that's resting on a horizontal frictionless floor and we apply a force causing the block to move by some displacement D the work done on the Box by the force is going to be be equal to the force multiplied by the... Read More

Key Insights

• 🫥 Work can be calculated by multiplying force and displacement or using the dot product formula.
• 💦 The work-energy theorem relates work to the change in kinetic energy of an object.
• 💦 Conservative forces contribute to the work done by causing a change in potential energy.
• 🫢 When dealing with gases, the work done by a gas can be calculated by multiplying the pressure and change in volume.
• ☠️ Power is the rate of energy transfer, calculated by dividing work by time.
• 💦 Energy is possessed by an object, while work is the mechanism of energy transfer.
• 💦 Power is related to work and time, with 1 watt representing the transfer of 1 joule of energy per second.
• ⌛ Kilowatts are a unit of power, while kilowatt-hours are a unit of energy used over a specific time period.

Questions & Answers

Q: How can you calculate the work done on a block when it is moved by a force on a frictionless floor?

The work done on the block can be calculated by multiplying the force applied to the block by the displacement of the block.

Q: How can the work done on a block pulled by a tension force in a horizontal direction be calculated?

The work done can be calculated using the dot product formula, which is the force multiplied by the displacement multiplied by the cosine of the angle between them.

Q: What is the work-energy theorem?

The work-energy theorem states that the work done by the net force on an object is equal to the change in its kinetic energy.

Q: How can the work done by conservative forces be calculated?

The work done by conservative forces, such as gravity or a spring, is equal to the negative change in potential energy.

Summary & Key Takeaways

• Work done on an object by a force can be calculated by multiplying the force and displacement, or using the dot product formula if the angle between the force and displacement vectors is known.

• Work is also equal to the change in kinetic energy of an object, following the work-energy theorem.

• Work done by conservative forces can be found by the negative change in potential energy, such as gravity or a spring.