Will a swim cap keep my hair dry?

Q: I’ve just started having Shaw Method swimming lessons. I like to go swimming 4 or 5 times a week but it means I have to wash my long hair every time and it takes ages to dry. I wondered if a swimming hat would (a) keep my hair dry and (b) not affect my swimming. I am enjoying swimming so much I want to go all the time.
Lesley, East Grinstead, West Sussex

Steven: A swimming cap is a great idea, although it will not be completely watertight, it will help to keep your hair dry. It will also help to keep water out of your ears. The cap will not affect your swimming at all.