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Velocity of star is 10^(6)m//s and frequ...

Velocity of star is `10^(6)m//s` and frequency of emitted light is `4.5X10^(14)Hz`. If star is moving away, then apparent frequency will be

A

`4.5Hz`

B

`4.5xx10^(16)Hz`

C

`4.485X10^(14)Hz`

D

`4.5X10^(8)Hz`

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To find the apparent frequency of light emitted by a star that is moving away from us, we can use the formula for the Doppler effect for light. The formula is given by: \[ \nu' = \nu \left(1 - \frac{v}{c}\right) \] Where: - \(\nu'\) = apparent frequency - \(\nu\) = emitted frequency - \(v\) = velocity of the star (moving away) - \(c\) = speed of light ### Step-by-Step Solution: 1. **Identify the given values:** - Velocity of the star, \(v = 10^6 \, \text{m/s}\) - Frequency of emitted light, \(\nu = 4.5 \times 10^{14} \, \text{Hz}\) - Speed of light, \(c = 3 \times 10^8 \, \text{m/s}\) 2. **Substitute the values into the Doppler effect formula:** \[ \nu' = 4.5 \times 10^{14} \left(1 - \frac{10^6}{3 \times 10^8}\right) \] 3. **Calculate the fraction \(\frac{v}{c}\):** \[ \frac{v}{c} = \frac{10^6}{3 \times 10^8} = \frac{1}{300} \approx 0.00333 \] 4. **Substitute this value back into the formula:** \[ \nu' = 4.5 \times 10^{14} \left(1 - 0.00333\right) \] \[ \nu' = 4.5 \times 10^{14} \times 0.99667 \] 5. **Calculate the apparent frequency:** \[ \nu' \approx 4.5 \times 10^{14} \times 0.99667 \approx 4.485 \times 10^{14} \, \text{Hz} \] ### Final Answer: The apparent frequency of the light emitted by the star moving away from us is approximately: \[ \nu' \approx 4.485 \times 10^{14} \, \text{Hz} \]

To find the apparent frequency of light emitted by a star that is moving away from us, we can use the formula for the Doppler effect for light. The formula is given by: \[ \nu' = \nu \left(1 - \frac{v}{c}\right) \] Where: - \(\nu'\) = apparent frequency ...
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