For galaxies in the Hydra cluster, the recessional velocity is 61,000 km/sec. Assuming the nonrelativistic solution, what is the shift in frequency for the Balmer H $\alpha$ line, the rest wavelength of which is 656.3 nm?

Question

Quizplus · Accepted Answer

The shift in frequency for the Balmer Hα line can be calculated using the Doppler shift formula for wavelengths, which is $\Delta \lambda = \lambda_0 \frac{v}{c}$, where $\Delta \lambda$ is the change in wavelength, $\lambda_0$ is the rest wavelength (656.3 nm for the Hα line), $v$ is the recessional velocity (61,000 km/s), and $c$ is the speed of light (approximately 300,000 km/s). Plugging in the values, we get $\Delta \lambda = 656.3 nm \times \frac{61,000 km/s}{300,000 km/s}$, which gives a shift of approximately 133 nm.

For Galaxies in the Hydra Cluster, the Recessional Velocity Is α\alphaα

For Galaxies in the Hydra Cluster, the Recessional Velocity Is $\alpha$