Arotating flywheel can be used as a method to store energy. if it is required that such a device be able to store up to a maximum of 1.00 ´ 106 j when rotating at 400 rad/s, what moment of inertia is required?

options:

1)

50 kg×m2

2)

25 kg×m2

3)

12.5 kg×m2

4)

6.3 kg×m2

5)

5.4 kg×m2

(3).I = 12.5 kg.m²

Explanation:

Given that

maximum stored energy E

E= 1 x 10⁶ J

Angular speed ,ω = 400 rad/s

We know that energy stored in flywheel given as

I=Moment of inertia of the flywheel

Now by putting the values

I = 12.5 kg.m²

Therefore the answer will be (3).

I = 12.5 kg.m²

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.