Question

A flywheel of mass 2 kg has radius of gyration 0.5m. If it makes 10 r.p.s. then its rotational kinetic energy will be ______.

Options

• 100π² erg

• 50π² J

• 100π² J

• 50π² erg

Answer 1

A flywheel of mass 2 kg has radius of gyration 0.5m. If it makes 10 r.p.s. then its rotational kinetic energy will be 100π² J.

Explanation:

`"K.E." =1/2Iomega^2=1/2"mk"^2(2pi"f")^2`

`=1/2"mk"^2xx4pi^2"f"^2=1/2xx2xx(0.5)^2xx4pi^2xx(10)^2`

= 100π² J