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Karnataka Board PUCPUC Science Class 11

State if the following statement is true or false. Give a reason for your answer. Total energy of a system is always conserved, no matter what internal and external forces on the body are present.

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Question

State if the following statement is true or false. Give a reason for your answer. 

Total energy of a system is always conserved, no matter what internal and external forces on the body are present.

Options

  • True

  • False

MCQ
True or False
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Solution

This statement is False.

Explanation:

Even though internal forces are in equilibrium and do not perform work on a body, it is the external forces that possess the capability to do work. Consequently, external forces can alter the energy state of a system.

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Chapter 5: Work, Energy and Power - EXERCISES [Page 89]

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NCERT Physics Part 1 and 2 [English] Class 11
Chapter 5 Work, Energy and Power
EXERCISES | Q 5.7 (b) | Page 89

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