Heat & Thermodynamics · JEE Main previous year questions

2010 2 questions

1. Q542010 · 25 Apr 2010 · Shift 1

   If a source of power $4\mathrm{kW}$ produces $10^{20}$ photons/second, the radiation belongs to a part of the spectrum called

   1. A.$X$-rays
   2. B.ultraviolet rays
   3. C.microwaves
   4. D.$\gamma$ - rays
   Show answer

   Answer: A

2. Q592010 · 25 Apr 2010 · Shift 1

   A diatomic ideal gas is used in a Carnot engine as the working substance. If during the adiabatic expansion part of the cycle the volume of the gas increases from $V$ to $32V$, the efficiency of the engine is

   1. A.0.5
   2. B.0.75
   3. C.0.99
   4. D.0.25
   Show answer

   Answer: B