The supply voltage to a room is 120 V. The resistance of the lead wires is 6 . A 60 W bulb is already switched on. What is the decrease of voltage across the bulb, when a 240 W heater is switched on in parallel to the bulb?
10.04 Volt
Zero Volt
2.9 Volt
13.3 Volt
As discussed in
Power dissipiated in external resistance -
-
Power of heater =
Voltage across bulb before heater switched on
When Heater and bulb in parallel then
Voltage across bulb after heater switched on:
Option 1)
10.04 Volt
Option 2)
Zero Volt
Option 3)
2.9 Volt
Option 4)
13.3 Volt
Study 40% syllabus and score up to 100% marks in JEE