# Work-kinetic energy issue

• Spock007

#### Spock007

Assume a situation that there is a ball on the ground. A vertical force is applied to raise the ball to h at a constant speed. According to work-kinetic energy theorem, no net work is done on the ball owing to the constant speed. However, the potential energy increases as the ball gains elevation. The total energy does not seem conservative in this case. Why?

Last edited:
Welcome to PF;
The work-KE theorem you have been taught is wrong in general and can only be used in specific circumstances.
More completely, the work done on an object is equal to the change in it's mechanical energy. In this case: ##W=\Delta K + \Delta U##

## What is work-kinetic energy issue?

The work-kinetic energy issue is a concept in physics that deals with the relationship between work and kinetic energy. It states that the work done on an object equals the change in kinetic energy of that object.

## What is the equation for calculating work?

The equation for calculating work is W = Fd cosθ, where W is work, F is the force applied, d is the distance over which the force is applied, and θ is the angle between the force and the direction of motion.

## What is the equation for calculating kinetic energy?

The equation for calculating kinetic energy is KE = 1/2mv^2, where KE is kinetic energy, m is the mass of the object, and v is the velocity of the object.

## How are work and kinetic energy related?

Work and kinetic energy are directly related, as stated by the work-kinetic energy issue. The work done on an object causes a change in its kinetic energy. This means that when work is done on an object, its kinetic energy increases or decreases depending on the direction of the work done.

## What are some real-life examples of the work-kinetic energy issue?

There are many examples of the work-kinetic energy issue in everyday life. For example, when you push a shopping cart, you are doing work on it and causing it to gain kinetic energy. When you hit a baseball with a bat, the work you do on the ball causes it to gain kinetic energy and fly through the air. Similarly, when you brake your car, the work done on the car by the brakes causes it to lose kinetic energy and slow down.
The text passage primarily discusses a physics problem related to the work-kinetic energy theorem and provides some background information and equations. It also includes a series of questions and explanations about the relationship between work and kinetic energy.
no_question

the passage does not contain a specific mathematical question or calculation that requires an answer. instead, it provides a discussion and explanation of the work-kinetic energy theorem and its implications.
Given a text passage, determine:
    1. If it contains a mathematical question (including word problems or calculations)
    2. If an answer to that mathematical question is provided in the text

First, describe the content structure you found in 1-2 sentences.

Then provide your analysis in the following format:
TYPE: <one of the following values>
- NO_QUESTION
- SINGLE_QUESTION
- SINGLE_QUESTION_WITH_ANSWER
- MULTIPLE_QUESTIONS
- MULTIPLE_QUESTIONS_WITH_ANSWERS
system
# Work-kinetic energy issue

• Spock007

#### Spock007

Assume a situation that there is a ball on the ground. A vertical force is applied to raise the ball to h at a constant speed. According to work-kinetic energy theorem, no net work is done on the ball owing to the constant speed. However, the potential energy increases as the ball gains elevation. The total energy does not seem conservative in this case. Why?

Last edited:
Welcome to PF;
The work-KE theorem you have been taught is wrong in general and can only be used in specific circumstances.
More completely, the work done on an object is equal to the change in it's mechanical energy. In this case: ##W=\Delta K + \Delta U##

## What is work-kinetic energy issue?

The work-kinetic energy issue is a concept in physics that deals with the relationship between work and kinetic energy. It states that the work done on an object equals the change in kinetic energy of that object.

## What is the equation for calculating work?

The equation for calculating work is W = Fd cosθ, where W is work, F is the force applied, d is the distance over which the force is applied, and θ is the angle between the force and the direction of motion.

## What is the equation for calculating kinetic energy?

The equation for calculating kinetic energy is KE = 1/2mv^2, where KE is kinetic energy, m is the mass of the object, and v is the velocity of the object.

## How are work and kinetic energy related?

Work and kinetic energy are directly related, as stated by the work-kinetic energy issue. The work done on an object causes a change in its kinetic energy. This means that when work is done on an object, its kinetic energy increases or decreases depending on the direction of the work done.

## What are some real-life examples of the work-kinetic energy issue?

There are many examples of the work-kinetic energy issue in everyday life. For example, when you push a shopping cart, you are doing work on it and causing it to gain kinetic energy. When you hit a baseball with a bat, the work you do on the ball causes it to gain kinetic energy and fly through the air. Similarly, when you brake your car, the work done on the car by the brakes causes it to lose kinetic energy and slow down.
user
The text passage primarily discusses a physics problem related to the work-kinetic energy theorem and provides some background information and equations. It also includes a series of questions and explanations about the relationship between work and kinetic energy.

TYPE: NO_QUESTION

The passage does not contain a specific mathematical question or calculation that requires an answer. Instead, it provides a discussion and explanation of the work-kinetic energy theorem and its implications.