question_answer

The resistance of hot tungsten filament is about 10 times the cold resistance. What will be the resistance of 100 W and 200 V lamp, when not in use?     AIEEE  Solved  Paper-2005

A) \[40\,\Omega \]

B)                                        \[20\,\Omega \]              

C)        \[400\,\Omega \]            

D)        \[200\,\Omega \]

Correct Answer: A

Solution :

As power