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The amplitude of damped oscillator becom...

The amplitude of damped oscillator becomes `1/3` in `2s`. Its amplitude after `6s` is `1//n` times the original. The value of `n` is

A

`3^(2)`

B

`root(3)(2)`

C

`root(3)(3)`

D

`3^(3)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the behavior of a damped oscillator and use the provided information to find the value of \( n \). ### Step-by-Step Solution: 1. **Understanding the Damped Oscillator Equation**: The amplitude \( A(t) \) of a damped oscillator at time \( t \) can be expressed as: \[ A(t) = A_0 e^{-\lambda t} \] where \( A_0 \) is the initial amplitude and \( \lambda \) is the damping constant. 2. **Setting Up the First Condition**: According to the problem, the amplitude becomes \( \frac{1}{3} A_0 \) after \( 2 \) seconds. We can set up the equation: \[ A(2) = A_0 e^{-2\lambda} = \frac{1}{3} A_0 \] Dividing both sides by \( A_0 \) (assuming \( A_0 \neq 0 \)): \[ e^{-2\lambda} = \frac{1}{3} \] This is our **Equation (1)**. 3. **Setting Up the Second Condition**: The problem states that after \( 6 \) seconds, the amplitude is \( \frac{1}{n} A_0 \). We can express this as: \[ A(6) = A_0 e^{-6\lambda} = \frac{1}{n} A_0 \] Again, dividing both sides by \( A_0 \): \[ e^{-6\lambda} = \frac{1}{n} \] This is our **Equation (2)**. 4. **Relating the Two Equations**: From **Equation (1)**, we have: \[ e^{-2\lambda} = \frac{1}{3} \] We can express \( e^{-6\lambda} \) in terms of \( e^{-2\lambda} \): \[ e^{-6\lambda} = (e^{-2\lambda})^3 = \left(\frac{1}{3}\right)^3 = \frac{1}{27} \] 5. **Substituting into Equation (2)**: Now substituting \( e^{-6\lambda} \) into **Equation (2)**: \[ \frac{1}{27} = \frac{1}{n} \] This implies: \[ n = 27 \] ### Final Answer: The value of \( n \) is \( 27 \).
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