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Current Electricity — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity1 Mark
MCQ
For two statements are given$-$one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: ln a chain of bulbs, $50$ bulbs are joined in series. One bulb is removed now the circuit is again completed. If the remaining $49$ bulbs are again connected in series across the same supply, then light gets decreased in the room.
Reason: The resistance of $49$ bulbs will be more than $50$ bulbs.
  • A
    Both $A$ and $R$ are true, and $R$ is the correct explanation of $A.$
  • B
    Both $A$ and $R$ are true, but $R$ is not the correct explanation of $A.$
  • C
    $A$ is true, but $R$ is false.
  • ✓
    $A$ is false and $R$ is also false.
✓

Answer

Correct option: D.
$A$ is false and $R$ is also false.
Since the bulbs are joined in series, so when one bulb is removed from chain then the resistance of the chain is decreased, hence current flowing through each bulb is increased. As heat produced ee $i^2$, hence light gets increased in the room.

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