Question

A Frisbee flies across a field. Determine if the system has translational kinetic energy, rotational kinetic energy, neither, or both as determined by the observer in each of the following cases.

The observer watches the flight of the Frisbee across the field from a park bench.
a. translational kinetic energy
b. rotational kinetic energy
c. neither
d. both

Answer 1

The Frisbee in motion has both translational and rotational kinetic energy, as it moves across the field and spins around its axis.

Step-by-step explanation:

When observing a Frisbee flying across a field from a park bench, we can determine that the Frisbee has both translational and rotational kinetic energy. The Frisbee's movement from one location to another, following a straight path, gives it translational kinetic energy. Simultaneously, the spinning of the Frisbee around its own axis as it moves through the air contributes to its rotational kinetic energy. This situation is similar to a bike tire: while being ridden down a bike path, the tire exhibits rotational kinetic energy because of its spinning motion and translational kinetic energy due to the bike's forward movement. However, if the front wheel spins while the bike remains stationary, it demonstrates only rotational kinetic energy relative to the Earth.