Recall the formula of the first law of thermodynamics in terms of change in internal energy and work done by the system, ΔU=Q−W, given, ΔU=2500J, Q=606000×t=(100t)J and W=P×t=90t,
⇒2500J=100tJ−90tJ⇒t=2.5×102s.
JEE Main 2021 — Physics Thermodynamics
An electric appliance supplies 6000Jmin−1, heat to the system. If the system delivers a power of 90W. How long it would take to increase the internal energy by 2.5×103J?
Held on 26 Aug 2021 · Verified 6 Jul 2026.
2.5×101s
2.5×102s
2.4×103s
4.1×101s
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