Answer:
25 J
Explanation:
Rotational kinetic energy (RE) is half the moment of inertia (I) times the square of the angular speed (ω). First, convert the angular speed to radians per second.
ω = 4.6 rev/s × (2π rad/rev)
ω = 9.2π rad/s
Calculate the rotational kinetic energy.
RE = ½ Iω²
RE = ½ (0.060 kg m²) (9.2π rad/s)²
RE ≈ 25 J
Rounded to two significant figures, the rotational kinetic energy is approximately 25 Joules.