The change of color. Each color has a different wavelength therefore a different frequency.
In order to find which rational number is between 0 and 1, let's convert them into their decimal form:

Looking at the numbers in their decimal form, we can see that the number between 0 and 1 is one-fourth, therefore the correct option is the second one.
It seems like the question is asking for the frequency.
Given:
Time period (T) = 2.4 sec
Frequency (f) =?
We know that the formula for frequency is:
Frequency (f) = 1/time period (T)
= 1 / 2.4 s
= 0.42 Hz. is the frequency for this problem.
Answer:
E) True. The girl has a larger tangential acceleration than the boy.
Explanation:
In this exercise they do not ask us to say which statement is correct, for this we propose the solution to the problem.
Angular and linear quantities are related
v = w r
a = α r
the boy's radius is r₁ = 1.2m the girl's radius is r₂ = 1.8m
as the merry-go-round rotates at a constant angular velocity this is the same for both, but the tangential velocity is different
v₁ = w 1,2 (boy)
v₂ = w 1.8 (girl)
whereby
v₂> v₁
reviewing the claims we have
a₁ = α 1,2
a₂ = α 1.8
a₂> a₁
A) False. Tangential velocity is different from zero
B) False angular acceleration is the same for both
C) False. It is the opposite, according to the previous analysis
D) False. Angular acceleration is equal
E) True. You agree with the analysis above,
Answer:The magnetic field around an electromagnet is just the same as the one around a bar magnet. It can, however, be reversed by turning the battery around. Unlike bar magnets, which are permanent magnets, the magnetism of electromagnets can be turned on and off just by closing or opening the switch.