The internal energy change in a system that has absorbed 2 kcals of heat

The internal energy change in a system that has absorbed 2 kcals of heat and done 500J of work is:

Options

(a) 6400 J
(b) 5400 J
(c) 7900 J
(d) 8900 J

Correct Answer:

7900 J

Explanation:

According to first law of thermodynamics Q = ∆U + W
∆U = Q – W = 2 x 4.2 x 1000 – 500 = 8400 – 500 = 7900 J

admin:

Related Questions

  1. A coil has an area of 0.05 m² and it has 800 turns. It is placed perpendicularly
  2. A potentiometer wire of length 10 m and resistance 10 Ω per metre is connected in series
  3. A transistor is operated in common emitter configuration at constant collector
  4. The self-inductance of a coil having 500 turns is 50mH. The magnetic flux
  5. Electrons used in an electron microscope are accelerated by a voltage of 25 kV