Question on: JAMB Physics - 2024

5 x 10-3 kg of liquid at its boiling point is evaporated in 20 s by the heat generated by a resistor of 2 Ω when a current of 10 A is used. The specific latent heat of vaporization of the liquid is

A

8.0 x 104 J/kg

B

8.0 x 105 J/kg

C

8.0 x 106 J/kg

D

8.0 x 107 J/kg

Ask EduPadi AI for a detailed answer
Correct Option: B

Here's how to solve the problem:

  1. Calculate the heat energy generated by the resistor:
    • The power (P) dissipated by a resistor is given by P = I²R, where I is the current and R is the resistance.
    • P = (10 A)² * 2 Ω = 200 W
    • The heat energy (Q) generated in 20 seconds is Q = P * t, where t is time.
    • Q = 200 W * 20 s = 4000 J
  2. Calculate the specific latent heat of vaporization (L):
    • The heat energy (Q) used to evaporate the liquid is given by Q = mL, where m is the mass of the liquid and L is the specific latent heat of vaporization.
    • L = Q / m
    • L = 4000 J / (5 x 10-3 kg) = 8.0 x 105 J/kg

Add your answer

Notice: Please post responsibly.

Please share this, thanks!

No responses