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Delta v

by Miraj Kayastha
Tags: change in velocity, delta
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Miraj Kayastha
#1
Feb11-14, 07:45 AM
P: 68
If the velocity of the object of 5 kg changed from 5 m/s to 4 m/s. Then is the change in kinetic energy -22.5 J or +22.5J.

doesn't change mean final velocity minus initial velocity?
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ZapperZ
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Feb11-14, 07:56 AM
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Quote Quote by Miraj Kayastha View Post
If the velocity of the object of 5 kg changed from 5 m/s to 4 m/s. Then why isn't the change change in kinetic energy -22.5 J. The correct answer is +22.5J.

doesn't change mean final velocity minus initial velocity?
This is vague. This is obviously from a HW/Coursework question, which you are not telling us. The "change" depends on the OBJECT IN QUESTION. Is this really the change in KE of the object that slowed down, or the change in KE of another entity that absorbed this energy change? Without you giving us the full picture, we can't tell.

If this is related to school work, please continue by presenting the full question, and what you have attempted, in the HW/Coursework forum.

Zz.
Doc Al
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Feb11-14, 08:37 AM
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Quote Quote by Miraj Kayastha View Post
If the velocity of the object of 5 kg changed from 5 m/s to 4 m/s. Then is the change in kinetic energy -22.5 J or +22.5J.
Well, does the KE of the object increase or decrease?

doesn't change mean final velocity minus initial velocity?
Change in any quantity generally means 'final value' - 'initial value'.


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