Question

A goldfish swims through an aquarium by moving its fins and tail. What causes the fish to move forward?
I. The force exerted by the water on the goldfish
II. The force exerted by the tail of the goldfish on the water
III. The force exerted by the fins of the goldfish on the water

• A. I only
• B. II only
• C. I and III only
• D. II and III only
• E. I, II, and III

Answer 1

Answer: (E)

I, II, and III

The fins and tail of goldfish exert force on the water in the backward direction and according to Newton's 3rd law of motion, the water exerts the same force on the goldfish in forward direction which helps it to swim in forward direction.