A fly wheel rotating about fixed axis has a kinetic energy of 360 joule when its angular speed is 30 radian/sec. The moment of inertia of the wheel about the axis of rotation is

Question

A fly wheel rotating about fixed axis has a kinetic energy of 360 joule when its angular speed is 30 radian/sec. The moment of inertia of the wheel about the axis of rotation is (A) 0.6 kgm2 (B) 0.15 kgm2 (C) 0.8 kgm2 (D) 0.75 kgm2

Tardigrade Admin · Accepted Answer

K.E. = (1/2)Iω2 I=(2K.E/ω2)=(2 × 360/30 × 30)=0.8 kgm2

Q. A fly wheel rotating about fixed axis has a kinetic energy of $360$ joule when its angular speed is $30$ radian/sec. The moment of inertia of the wheel about the axis of rotation is

$0.6 k g m^{2}$

$0.15 k g m^{2}$

$0.8 k g m^{2}$

$0.75 k g m^{2}$

$K . E . = \frac{1}{2} I ω^{2}$
$I = \frac{2 K . E}{ω ^{2}} = \frac{2 \times 360}{30 \times 30} = 0.8 k g m^{2}$

Q. A fly wheel rotating about fixed axis has a kinetic energy of 360 joule when its angular speed is 30 radian/sec. The moment of inertia of the wheel about the axis of rotation is

0.6kgm2

0.15kgm2

0.8kgm2

0.75kgm2