Doppler Effect Calculations

An astronomer looks at a star in the night sky. Based on his calculations the star's light is shifting towards the color blue. What does this mean about the star?

When an ambulance move TOWARD you it sounds ________ pitched. 

When a car moves towards you, the sound of its horn seems relatively...

The top spectra is the laboratory spectra and is not moving. What type of shift is shown with the bottom spectra and is the object moving towards or away from the observer?

As objects move in space, their wavelengths change. This phenomenon is called the...

A train is moving towards a stationary observer at a speed of 30 m/s. The frequency of the train's whistle is 500 Hz. What frequency does the observer hear? (Assume the speed of sound is 340 m/s)

An ambulance is moving away from you with its siren on. If the original frequency of the siren is 700 Hz and you hear it at 650 Hz, what can you infer about the speed of the ambulance? (Assume the speed of sound is 340 m/s)

A star is moving away from Earth at a high speed. If the light from the star is observed to be redshifted, what does this indicate about the star's motion?

A car is approaching a stationary observer with a horn frequency of 400 Hz. If the observer hears a frequency of 420 Hz, what is the speed of the car? (Assume the speed of sound is 340 m/s)

If a sound source is moving at the speed of sound, what is the observed frequency by a stationary observer?