Cosmology x

Question 1

Explain what has to happen for the passage of time to be measured, giving an expample

Answer 1

Something has to change for the passage of time to be measure
E.g. the apparent position of the sun in the sky

Question 2

Explain what is meant by the arrow of time

Answer 2

Time only moves forward, not backwards. This is because the universe naturally moves from a state of order to disorder and not the reverse

Question 3

Define entropy giving an example

Answer 3

Entropy is a measure of disorder

E.g. a sandcastle has low entropy because it is ordered ( less ways it could be arranged)

A pile of sand has Hugh entropy because it is disordered (lots of ways it could be arranged)

Question 4

How is the entropy of the universe changing over time

Answer 4

The universe is moving from low entropy (order) to high entropy (disorder)