Practice question · Numerical answer
A gas absorbs 500 J of heat and does 300 J of work pushing its piston out. By how much does its internal energy change, in joules?
Hints
- First law: .
- Energy in as heat, minus energy out as work.
Show the answer
200 (answers within ±1 count)
Why
J. The first law is nothing but energy bookkeeping: heat and work are the only two currencies, and is the account balance.
Practise First Law of Thermodynamics
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