Doppler Effect in Light and Sound

The video explains the Doppler effect, starting with sound waves, where the pitch changes as a sound source moves relative to an observer. It then extends the concept to light waves, showing how the spectrum of a star shifts depending on its movement towards or away from us, known as blue-shift and redshift. The video concludes by discussing how these shifts help measure the speed and rotation of stars and detect binary star systems.

What common experience demonstrates the Doppler Effect?

• The change in speed of a moving vehicle

• The change in color of a traffic light

• The change in pitch of a car horn as it moves past

• The change in temperature when a car passes by

How does the pitch of a sound change as the source moves towards an observer?

• The pitch remains the same

• The pitch becomes lower

• The pitch fluctuates randomly

• The pitch becomes higher

What happens to sound waves as the source moves away from the observer?

• The sound waves disappear

• The sound waves become louder

• The sound waves are stretched out

• The sound waves are compressed

What is the term used when light from an approaching star shifts to shorter wavelengths?

• Greenshifted

• Blueshifted

• Yellowshifted

• Redshifted

What is observed when light from a receding star shifts to longer wavelengths?

• The light is blueshifted

• The light is yellowshifted

• The light is redshifted

• The light is greenshifted

What is the key to measuring the Doppler Effect in light?

• The change in temperature of the star

• The change in position of the spectral lines

• The change in size of the star

• The change in brightness of the light

Which of the following can be determined using the Doppler Effect in astronomy?

• The color of a star

• The age of a star

• The velocity of a star moving towards or away from us

• The size of a star

How can the Doppler Effect help in understanding binary stars?

• By detecting and measuring their orbital motion

• By determining their color

• By measuring their temperature

• By calculating their distance from Earth