First slide
Thermal effect of current
Question

Three electric bulbs rated 40, 60 and 100 watts respectively are connected in parallel with 230 volts d.c. mains. The current (in amp) through the 60 W bulb and the effective resistance (in ohm) of the circuit will be respectively, approximately:

Moderate
Solution

R=v2P1Req=1V2P1+P2+P3Req=230×23040+60+100=230×230200=265Ω

 Current in 60W bulb =PV=60230=0.26amp

Get Instant Solutions
When in doubt download our app. Now available Google Play Store- Doubts App
Download Now
Doubts App