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. 64 identical spheres of charge q and capacitance C each are combined to form a large
  2. If a charge in current of 0.01 A in one coil produces a change in magnetic flux
  3. A 0.01 H inductor and √3 πΩ resistance are connected in series
  4. When a mass m is attached to a spring, it normally extends by 0.2 m.
  5. A body of mass m is placed on the earth’s surface. It is taken from the earth’s surface