Question

The star Sirius is moving toward us at 7600 m/s . A line in its spectrum has a frequency of 5.71*10^14 Hz when stationary. How much will the frequency of the line be shifted?

Answer 1

Answer:

1.33 * 10⁻¹¹metres

Explanation:

Using the relationship to determine the amount by which the frequency of the line be shifted $v = f\lambda$

v = velocity of the moving star = 7600m/s

f = frequency of the line spectrum = 5.71*10^14 Hz

from the formula;

$\lambda = \frac{v}{f}\\ \lambda = \frac{7600}{5.71*10^{14} } \\\lambda = \frac{7.6*10^{3} }{5.71*10^{14} }\\\lambda = 1.33*10^{-11}m$

The frequency of the line will be shifted by 1.33 * 10⁻¹¹metres