All the heat generated by a current of 2A passing through a resistor of 6Ω for 2.5s is used to evaporate 5 g of a liquid at its boiling point. What is the specific latent heat of the liquid?

All the heat generated by a current of 2A passing through a resistor of 6Ω for 2.5s is used to evaporate 5 g of a liquid at its boiling point. What is the specific latent heat of the liquid?

A 60 Jg^-1
B 120 Jg^-1
C 300 Jg^-1
D 360 Jg^-1
E 1500 Jg^-1

waec 1989 physics

The correct answer is B. 120 Jg^-1

Electrical Energy = Heat Energy.

I²Rt = ml

2² x 6 25 = 5 x L.

L = 120 Jg^-1.

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