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Course: Class 11 Physics (India) > Unit 16

Lesson 1: Zeroth and first law of thermodynamics
Science
Class 11 Physics (India)
Thermodynamics
Zeroth and first law of thermodynamics
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First law of thermodynamics: word problems

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Problem

When a certain amount water changes from liquid to vapor state, the work done by the molecules against the outside pressure is 480 J. In this process, the heat supplied to the system is 7500 J.
What percentage of the total heat goes into increasing the internal energy of the molecules?
Note: Report your answer correct to one decimal place
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
%