Question

Rosa fills a graduated cylinder with 100 milliliters of Liquid X. She fills another graduated cylinder with 100 milliliters of Liquid Y. Then, at the same time and from the same height, she drops a marble into each liquid. The marble hits the bottom of the cylinder containing Liquid Y first.

Which best explains this result?

Liquid X is more viscous than Liquid Y.
Liquid Y is more viscous than Liquid X.
Liquid X’s atoms have weaker attractive forces.
Liquid Y’s atoms have stronger attractive forces.

Answer 1

Liquid X is more viscous than Liquid Y.

A more viscous liquid produces greater internal resistance (drag) on the falling marble, so the marble moves more slowly in X and reaches the bottom later than the marble in the less viscous liquid Y.