The resistance of the filament of a lamp increases with the increase in temperature. $A$ lamp rated $100\, W, 220\, V$ is connected across a $220\, V$ power supply. If the voltage drops by $10\%$,then the power of the lamp will be:

  • A
    $90\, W$
  • B
    $81\, W$
  • C
    Between $90\, W$ and $100\, W$
  • D
    Between $81\, W$ and $90\, W$

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Match List-$I$ with List-$II$ and select the correct answer using the codes given below the lists.
List-$I$ List-$II$
$I$. Joule $A$. $\text{Henry} \times \text{Amp/sec}$
$II$. Watt $B$. $\text{Farad} \times \text{Volt}$
$III$. Volt $C$. $\text{Coulomb} \times \text{Volt}$
$IV$. Coulomb $D$. $\text{Oersted} \times \text{cm}$
$E$. $\text{Amp} \times \text{Gauss}$
$F$. $\text{Amp}^2 \times \text{Ohm}$

If in the circuit shown below,the internal resistance of the battery is $1.5 \, \Omega$ and $V_P$ and $V_Q$ are the potentials at $P$ and $Q$ respectively,what is the potential difference between the points $P$ and $Q$?

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Four lamps are connected as shown in the figure. When switch $S_2$ is open and switch $S_1$ is at position $2$,lamp $b$ is the brightest,and lamps $c$ and $d$ are the dimmest and have the same brightness. Now,if $S_2$ is closed and $S_1$ is at position $1$,what is the sequence of brightness of the lamps (starting from the brightest)?

In the circuit shown in the figure,find the current through the $4\,\Omega$ resistor.

The battery shown in the figure has an $e.m.f.$ $E$ and internal resistance $r$. The current in the circuit can be varied by sliding the contact $J$. If at any instant the current flowing through the circuit is $I$,the potential difference between the terminals of the cell is $V$,and the thermal power generated in the cell is equal to $\eta$ fraction of the total electrical power generated in it,then which of the following graphs is correct?

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