AP EAMCET202421 May 2024Morning ShiftPhysicsCurrent ElectricityActual
A lamp is rated at 240 ~V , 60 ~W . When in use the resistance of the filament of the lamp is 20 times that of cold filament. The resistance of the lamp when not in use is
Options
- A54
- B60
- C50
- D48
Correct answer
D. 48
Step-by-step solution
When the lamp is in use, aligned & R = V ^2 P = 240 240 60 =960 & R =20 R ^ R ^ = R 20 = 960 20 =48 aligned