Question

the lamps of rating 220v,60w and 220v, 100w are connected in series across 220v supply. calculate the voltage across each lamp and power consumption. what Will be the power consumption, if the two lamps are connected in parallel.​

Answer 1

answer: Power, P=V

2

R

R

1

=

50

220×220

=968Ω

R

2

=

100

220×220

=484Ω

The equivalent resistance in the circuit,

R

eq

=R

1

+R

2

R

eq

=968+484=1452Ω

The current flow in the circuit,

I=

1452

440

=0.3030A

The voltage drop across bulb 1.

V

1

=iR

1

=0.3030×968=293.33V

The voltage drop across bulb 2.

V

2

=iR

2

=0.3030×484=146.65V

Bulb 1 will be fused because it can tolerate only 220 V but the voltage drop across it is 293.33V