Energy, Work & Power (17 of 31) Work Energy Principle, Net Work Done on an Object

TL;DR

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

Transcript

okay in today's video we're gonna go over a problem involving the work-energy theorem and that is that the network is equal to the change in kinetic energy and this is the problem that we have sitting board in the cafeteria one day little Susie decides she's going to try and start a food fight it's some action going to do this she's going to pick u... Read More

Key Insights

• 💦 The work-energy theorem states that the work done on an object is equal to the change in kinetic energy.
• 😣 Initial kinetic energy is zero when an object is at rest.
• 🥰 Final kinetic energy can be calculated using the formula 1/2 mv^2, where m is the mass and v is the velocity.
• 💦 The video shows that the calculated final kinetic energy of the apple is equal to the work done on it by Susie.
• 💦 By knowing the mass and final velocity of the apple, the video determines the amount of work done by Susie as 34.3 joules.
• 💦 The work is a scalar quantity that is measured in joules.
• 😒 The video emphasizes the use of the work-energy theorem when the force and distance are not provided.

Questions & Answers

Q: What problem is discussed in the video?

The video discusses a problem involving the calculation of work done by Susie on an apple she throws using the work-energy theorem.

Q: How is the work-energy theorem used to solve the problem?

The work-energy theorem states that the work done on an object is equal to the change in kinetic energy. By calculating the change in kinetic energy of the apple, the video determines the work done by Susie.

Q: How is the initial velocity of the apple relevant to the problem?

The initial velocity of the apple is zero, as it is initially at rest before being thrown. This information is used to calculate the change in kinetic energy and the work done on the apple.

Q: What is the formula for calculating work?

The formula for calculating work is work = force × distance × cosine(theta). However, in this problem, the force and distance are not given, making it necessary to use the work-energy theorem instead.

Summary & Key Takeaways

• The video discusses a problem involving the work-energy theorem, where the task is to calculate the amount of work done by Susie on an apple she throws.

• Using the work-energy theorem, the video explains that the change in kinetic energy of the apple is equal to the amount of work done on it.

• By calculating the final kinetic energy of the apple, the video determines that the work done by Susie is 34.3 joules.