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QNEET-2024-Ph-154: NEET 2024 Physics - Class 12 NEET-2024-Ph-154 Solution: The amplitude of the charge oscillating in a circuit decreases…

The amplitude of the charge oscillating in a circuit decreases exponentially as Q=Q0e−Rt/2LQ = Q_0 e^{-Rt/2L} where Q0Q_0 is the charge at t=0 s. The time at which charge amplitude decreases to 0.50Q00.50Q_0 is nearly: [Given that R=1.5ΩL=12 mHln⁡(2)=0.693R=1.5\Omega L=12\ \text{mH} \ln(2)=0.693] 19.01 ms 11.09 ms 19.01 s 11.09 s

Multiple Choice Options

  • A 19.01 ms
  • B 11.09 ms
  • C 19.01 s
  • D 11.09 s

Step-by-Step Verified Solution

The given equation for the amplitude of the charge oscillating in a circuit is: Q = Q 0 e _ R t 2 L We need to find the time, t , at which charge amplitude decreases to 0.50 Q 0 . So, we set Q = 0.50 Q 0 : 0.50 Q 0 = Q 0 e _ R t 2 L Divide both sides by Q 0 : 0.50 = e _ R t 2 L Take the natural logarithm on both sides to solve for t : ln _ ( 0.50 ) = _ R t 2 L Recall that ln _ ( 0.50 ) = _ ln _ ( 2 ) . Substituting the given value ln _ ( 2 ) = 0.693 , we get: _ 0.693 = _ R t 2 L Remove the negative signs from both sides: 0.693 = R t 2 L Now, solve for t : t = 2 L _ 0.693 R Substituting the given values R = 1.5 � and L = 12   mH = 12 _ 10 _ 3   H , we have: t = 2 _ 12 _ 10 _ 3 _ 0.693 1.5 Calculate the numerator and denominator: t = 16.632 _ 10 _ 3 1.5 Finally, compute the value of t : t = 11.09 _ 10 _ 3   s = 11.09   ms Therefore, the time at which the charge amplitude decreases to 0.50 Q 0 is nearly 11.09 ms. Thus, the correct answer is: Option B: 11.09 ms

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