Question

Two resistances R and 2R are connected in parallel in an electric circuit. The thermal energy developed in R and 2R are in the ratio _______________ .

Options

• 1 : 2

• 2 : 1

• 1 : 4

• 4 : 1

Answer 1

2 : 1

 

Thermal energy developed in the resistances,

H = \[\frac{V^2}{R}t\]

Heat developed in the resistance R, H₁= \[\frac{V^2}{R}t\]

Heat developed in the resistance 2R, H₂ = \[\frac{V^2}{2R}t\]

Thus, Heat developed in the resistance R and 2R are in ratio 2 : 1.