GCSE Physics - What is Red Shift? #87

The video explains the concept of the universe expanding, evidenced by the redshift of light from distant galaxies. It introduces absorption spectra to understand redshift and uses a balloon model to illustrate how space itself expands, causing galaxies to appear as if they are moving away. The video concludes with a discussion on the Big Bang theory, proposing that the universe began from a tiny, dense, and hot state, expanding rapidly to its current form.

What is the relationship between the distance of a galaxy and its apparent speed of movement away from us?

What limitations exist when using models to represent the universe, as mentioned in the text?

Summarize the Big Bang theory and its significance in understanding the universe's expansion.