I believe A. is the answer. Temperature is the measure of heat, heat is considered to be the amount of vibration within an atom. Hot atoms will vibrate a lot, cooler atoms will no vibrate much. You can heat atoms up and cause them to break their bonds with other atoms and create liquids or gases. Hence, you can cool atoms and cause them to revert into a liquid from a gas, or solid from a liquid.
Frequency and wavelength are inversely proportional to each other. The wave with the greatest frequency has the shortest wavelength. Twice the frequency means one-half the wavelength. For this reason, the wavelength ratio is the inverse of the frequency ratio.
Assuming uniform angular acceleration, we can use the following kinematic equation in order to find the total angle rotated during the acceleration process, from rest to its operating speed:
Now, we need first to find the value of the angular acceleration, that we can get from the following expression:
Since the machine starts from rest, ω₀ = 0.
We know the value of ωf₁ (the operating speed) in rev/min.
Due to the time is expressed in seconds, it is suitable to convert rev/min to rev/sec, as follows:
Replacing by the givens in (2):
Solving for α:
Replacing (5) and Δt in (1), we get:
in order to get the number of revolutions during the first half of this period, we need just to replace Δt in (6) by Δt/2, as follows:
In order to get the number of revolutions rotated during the deceleration period, assuming constant deceleration, we can use the following kinematic equation:
First of all, we need to find the value of the angular acceleration during the second period.
We can use again (2) replacing by the givens:
ωf =0 (the machine finally comes to an stop)
ω₀ = ωf₁ = 57.5 rev/sec
Δt = 32 s
Solving for α in (9), we get:
Now, we can replace the values of ω₀, Δt and α₂ in (8), as follows:
In order to get finally the number of revolutions rotated during the first half of the second period, we need just to replace 32 s by 16 s, as follows: