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3. current electricity — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics3. current electricity1 Mark
MCQ
In meter bridge experiment for measuring unknown resistance ' $S$ ', the null point is obtained at a distance $30 cm$ from the left side as shown at point $D$. If $R$ is $5.6 k \Omega$, then the value of unknown resistance ' $S$ ' will be $\Omega .$
  • A
    $240$
  • B
    $24$
  • C
    $48$
  • ✓
    $2400$
✓

Answer

Correct option: D.
$2400$
d
$\frac{ S }{30}=\frac{5.6 \times 10^{3}}{70}$

$S =\frac{3}{7} \times 5.6 \times 10^{3}=2400$

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