Physics · May / June 2019 · Paper 11 · Question 20

The diagram shows air trapped in a flask by a small volume of water in a thin tube. When the flask is held in a student's hands, the small volume of water first moves down from P to Q, and then up to R. Why does the small volume of water move like this?

1. AThe flask contracts and then the air expands.
2. BThe flask expands and then the air contracts.
3. CThe flask expands and then the air expands less than the flask.
4. DThe flask expands and then the air expands more than the flask.

As printed in the paper