Question

Approximate Doppler shift formula for light is ______.

Options

• `(Delta nu)/nu = 2(v_"rad")/"c"`

• `(Delta nu)/nu = (v_"rad")/"c"`

• `(Delta nu)/nu = - (v_"rad")/"c"`

• `(Delta nu)/nu = - (v_"rad")/"2c"`

Answer 1

Approximate Doppler shift formula for light is `underline((Delta nu)/nu = - (v_"rad")/"c")`.

Explanation:

The fractional change in frequency Δν/ν is given by – `"v"_"radial"//"c"`, where `"v"_"radial"` is the component of the source velocity along the line joining the observer to the source relative to the observer. `"v"_"radial"` is considered positive when the source moves away from the observer.