The Doppler Effect and Origin of the Universe Flashcards
What are sound waves caused by?
Vibrations.
Why can’t sound travel in space?
There are no particles.
What are echoes?
Reflected sound waves.
What happens to sound waves when they travel through denser material?
They speed up.
What does the loudness of a sound depend on?
The larger the amplitude, the louder the sound.
What does the frequency affect?
The higher the frequency, the higher the pitch.
What is the evidence for an expanding universe?
More distant galaxies have greater red-shifts.
What is red-shift?
Light being shifted to lower frequencies as they travel through space.
If a source of waves moves towards you, how do the frequency and wavelength change?
Frequency seems higher. Wavelength seems shorter.
if a source of waves moves away from you, how do the frequency and wavelength change?
Frequency seems lower. Wavelength seems longer.
What is the Big Bang Theory?
- Singularity exploded 14 billion years ago
2. Expansion is still going on now
What is the other theory?
Steady State Theory.
What does the Steady State Theory state?
- Universe has always existed this way
2. Matter is being created as universe expands
Why is the Big Bang theory more likely?
It can explain cosmic microwave background radiation.
What is CMBR?
Low frequency electromagnetic radiation coming from all parts of the universe.
