Energy is to be stored in an 86.4 kg flywheel in the shape of a uniform solid disk. The moment of inertia (I) of the flywheel can be calculated using the formula I = mR^2, where m is the mass of the flywheel and R is the radius of the flywheel.
Given:
m = 86.4 kg
R = 1.25 m
Using the formula, we can calculate the moment of inertia:
I = (86.4 kg)(1.25 m)^2
To prevent structural failure of the flywheel, the maximum allowed radial acceleration (a) of a point on its rim is given as 3500 m/s^2.
The maximum kinetic energy (K) that can be stored in the flywheel can be calculated using the formula K = (1/2)Iω^2, where ω is the angular velocity of the flywheel.
To find ω, we can use the formula a = ω^2R, where a is the radial acceleration and R is the radius of the flywheel.
Given:
a = 3500 m/s^2
R = 1.25 m
Using the formula, we can calculate ω:
3500 m/s^2 = ω^2(1.25 m)
ω^2 = 3500 m/s^2 / 1.25 m
ω^2 = 2800 s^-2
ω = √(2800 s^-2)
Now that we have ω, we can calculate the maximum kinetic energy:
K = (1/2)(86.4 kg)(1.25 m)^2(√(2800 s^-2))^2
The answer options are given in scientific notation with SI units.