Hi there!
Angular momentum is equivalent to:

L = angular momentum (kgm²/s)
I = moment of inertia (kgm²)
ω = angular velocity (rad/sec)
Plug in the given values for moment of inertia and angular speed:

Translating the first sentence into equation we get, t = k(1/h)
where t is time in seconds, k is the constant and h is the horsepower. Substituting
the values in the equation we have, 12s = k(1/200) we have a k = 2400 seconds –
hp. To get the time at 240 hp we use the equation above and the constant, we
get, t = (2400 seconds-hp)(1/240hp) t = 10seconds.
Answer: I think the answer is a wave/ a transverse wave, or electromagnetic waves as well.
13 is the mode because it is the number that appears most often
:)