JEE Main & Advanced Physics Current Electricity, Charging & Discharging Of Capacitors Question Bank Heating Effect of Current

  • question_answer A bulb rated at (100W ? 200V) is used on a 100V line. The current in the bulb is                                   [JIPMER 1999]

    A)            \[\frac{1}{4}\]amp            

    B)            4 amp

    C)            \[\frac{1}{2}\]amp            

    D)            2 amp

    Correct Answer: A

    Solution :

                       \[P=\frac{{{V}^{2}}}{R}\Rightarrow 100=\frac{{{(200)}^{2}}}{R}\] Þ \[R=\frac{4\times {{10}^{4}}}{{{10}^{2}}}=400\,\Omega \]            Now, \[i=\frac{V}{R}=\frac{100}{400}=\frac{1}{4}amp\]


You need to login to perform this action.
You will be redirected in 3 sec spinner