Two electric resistors have equal values of resistance R. Each can be operated with a power of 320 walts [w] at 220 volts. If the two resistors are connected in series to a 110 volts electric supply, then the power generated in each resistor is

Options

A. 90 watts
B. 80 watts
C. 60 watts
D. 20 watts

Answer

d

Explanation

Power, `P = (V^(2))/(R )`
`R = V^(2))/(P)`
Here, P = 320 watts
V = 220 volts
when the resistors are connected is series, then power developed across each resistor,
`P' ((V)^(2))/(R ) = (((100)/(2))^(2))/(R ) =(110 xx 110)/(2 xx 2) xx (P)/(V^(2))`
`= (110 xx 110)/(2 xx 2) xx (320)/(220 xx 220)`
`= (1)/(4) xx (1)/(4) xx 320 = 20` walts