Rebecca Redding, age 9, of Enid, Okla., for her question:

WHAT MAKES A WHIRLPOOL?

A mass of water which spins around and around swiftly and with great force is called a whirlpool. It may occur when water current in a creek hits against a bank with a peculiar form. The water is then forced into a circular motion.

A whirlpool can also occur when opposing currents meet. Strong action of the wind can produce a whirlpool, and so can rocks that get in the way of a strong tide.

One of the world's most famous whirlpools is the one located in the gorge below the falls of the Niagara River. This whirlpool is caused by the wearing away of a side basin out of the line of the river's  course.

During storms, ocean whirlpools can become violent and dangerous to ships.