UV waves are the wave that is just above human eyesight from the naked eye. Ultra violet for real means more violet. As the radio waves, you will have to wait for the next commenter as I have no idea. Sorry!
Answer:
a) True
Explanation:
There are several possible explanations for this positive charge
* The explanation of the small positive charge in the plant when the bee approaches is like a defense system of the plants,
to prevent the bees from taking the pollen, but the flowers need the bees to transport the pollen for fertilization, so this possibility is not correct
* The air is conductive so the bee indexes a charge in the nearby air, this charge must be negative and this charge induced in the air induces a charge on the flower that must be positive.
When reviewing the different statements we have
a) True, it agrees with the second explanation of the phenomenon
b) False. The earth is a deposit of negative charge
c) false. If this is the case the charge should be negative
d) False. This residual charge from the other bees is quickly neutralized by the charge from the Earth.
You should calculate 40 kg and the radius 3mm.
(a) The frequency of water wave is 2 Hz.
(b) The wave speed of the water wave is 3.6 m/s.
<u>Explanation:</u>
(a) It is known that completion of one complete wave in 1 second is defined as frequency of 1 HZ. So here there are 120 waves crossing the boat in 1 minute. So the frequency of the water wave will be

As the time is 1 minute which is equal to 60 seconds and the number of waves is given as 120 then the frequency of the water wave is

So the frequency of water wave is 2 Hz.
(b) Then if the wavelength of the water wave is 1.8 m with a frequency of 2 Hz, then speed of the wave can be determined as the product of wavelength with frequency.
So Speed = Frequency × Wavelength
Speed = 2 × 1.8 = 3.6 m/s.
So the speed of the water wave is 3.6 m/s.