Delta v and change in velocity

AI Thread Summary
The discussion centers on the change in kinetic energy when a 5 kg object's velocity decreases from 5 m/s to 4 m/s. Participants debate whether the change in kinetic energy is -22.5 J or +22.5 J, emphasizing that "change" typically refers to final velocity minus initial velocity. There is confusion about whether the question pertains to the object's kinetic energy or the energy absorbed by another entity. Clarification is requested regarding the full context of the problem, as it influences the interpretation of the energy change. The conversation highlights the importance of understanding the relationship between velocity changes and kinetic energy calculations.
Miraj Kayastha
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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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Miraj Kayastha said:
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.
 
Miraj Kayastha said:
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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