Motion in a Plane Physics NCERT Exemplar Solutions Class 12th Chapter Six Physics NCERT Exemplar Solutions Class 12th Chapter Four Class 12th Physics

Time period of a simple pendulum in a stationary lift is 'T'. If the lift accelerated with $\frac{g}{6}$ vertically upwards then the time period will be:

(Where g = acceleration due to gravity)

Option 1 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mroot> <mrow> <mfrac> <mrow> <mn>6</mn> </mrow> <mrow> <mn>5</mn> </mrow> </mfrac> </mrow> <mrow></mrow> </mroot> <mi>T</mi> </mrow> </math> </span></p>

Option 2 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mroot> <mrow> <mfrac> <mrow> <mn>5</mn> </mrow> <mrow> <mn>6</mn> </mrow> </mfrac> </mrow> <mrow></mrow> </mroot> <mi>T</mi> </mrow> </math> </span></p>

Option 3 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mroot> <mrow> <mfrac> <mrow> <mn>6</mn> </mrow> <mrow> <mn>7</mn> </mrow> </mfrac> </mrow> <mrow></mrow> </mroot> <mi>T</mi> </mrow> </math> </span></p>

Option 4 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mroot> <mrow> <mfrac> <mrow> <mn>5</mn> </mrow> <mrow> <mn>6</mn> </mrow> </mfrac> </mrow> <mrow></mrow> </mroot> <mi>T</mi> </mrow> </math> </span></p>

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Answered by

Payal Gupta | Contributor-Level 10

6 months ago

Correct Option - 3

Detailed Solution:

$g_{e f f} = g + a$

$= g + \frac{g}{6}$

$= \frac{7 g}{6}$

$T' = 2 π \sqrt[]{\frac{l}{g_{e f f}}}$

$T' = \sqrt[]{\frac{6}{7}} T$

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Physics NCERT Exemplar Solutions Class 12th Chapter Six 2025

Physics NCERT Exemplar Solutions Class 12th Chapter Six 2025

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