Calculating Work: Doubling and Halving Velocity of a 40 Kg Wagon

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AI Thread Summary
To determine the work required to change the velocity of a 40 Kg wagon moving at 10 m/s, one must consider the work-energy principle, which states that work done is equal to the change in kinetic energy. Doubling the velocity to 20 m/s requires calculating the difference in kinetic energy, while halving it to 5 m/s involves a similar calculation. The user expresses confusion about needing additional information, such as applied force or friction, to solve the problem. However, the key point is that the work can be derived from the mass and the change in velocity. Understanding these principles is crucial for accurately calculating the work done in both scenarios.
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This is the question :|

A 40 Kg wagon is moving with a constant horizontal velocity of 10 m/s.
1. How much work must be done to double this velocity?
2. How much work must be done to halve the original velocity?

SOmeone please help me. :|
 
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nikechristo said:
This is the question :|

A 40 Kg wagon is moving with a constant horizontal velocity of 10 m/s.
1. How much work must be done to double this velocity?
2. How much work must be done to halve the original velocity?

SOmeone please help me. :|

Welcome to the PF, nikechristo. We do not do your work for you here on the PF. You must show your work before we can offer tutorial help. That's why there is a Homework Help posting template (which you deleted) that you should use to post your questions. There is a spot at the end to show your work so far.

So show us how you will approach these problems. What is the definition of work, in terms of forces and other things?
 
Thanks for your welcome berkeman. :) Sorry for deleting the default template. I'm new to this forum so i didn't know the rules and regulations.

Work is done on an object whenever a force makes something move. This is the definition of work.

The general equation of work done is W = Force applied * distance.

Homework Statement

\

A 40 Kg wagon is moving with a constant horizontal velocity of 10 m/s.
1. How much work must be done to double this velocity?
2. How much work must be done to halve the original velocity?

Homework Equations



W = Force applied * distance


The Attempt at a Solution



I don't get this question. I need the applied force or the force of friction to solve this question, rite? I don't think there is enough information to solve this, but i may be wrong. Is there a way to find the work done by using the mass and distance?
 
The work done is the change in kinetic energy.
 
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