The origin of the universe Flashcards
1
Q
What is the big bang theory?
A
The theory states that originally all the matter in the universe was concentrated into a single incredibly tiny point. This began to enlarge rapidly in a hot explosion (called the Big Bang), and it is still expanding today.
2
Q
When did the big bang supposedly happen?
A
The Big Bang happened about 13.7 billion years ago (that’s 13,700,000,000 years using the scientific definition of 1 billion = 1,000 million).
3
Q
What is the Doppler effect?
A
When an ambulance or police car goes past, its siren is high-pitched as it comes towards you, then becomes low-pitched as it goes away. This effect, where there is a change in frequency and wavelength, is called the Doppler effect.
