Answer:
The visible light frequency is 400 THz to 700 THz, approximately. A THz is a Terahertz, which is a unit of frequency equal to one trillion Hertz.
Explanation:
Given that,
Wavelength = 6.0 nm
de Broglie wavelength = 6.0 nm
(a). We need to calculate the energy of photon
Using formula of energy



(b). We need to calculate the kinetic energy of an electron
Using formula of kinetic energy


Put the value into the formula


(c). We need to calculate the energy of photon
Using formula of energy



(d). We need to calculate the kinetic energy of an electron
Using formula of kinetic energy


Put the value into the formula


Hence, This is the required solution.
The vacuum of outer space has essentially zero air. Because sound is just vibrating air, space has no air to vibrate and therefore no sound. If you are sitting in a space ship and another space ship explodes, you would hear nothing. So, in order for sound to travel, there has to be something with molecules for it to travel through. On Earth, sound travels to your ears by vibrating air molecules. In deep space, the large empty areas between stars and planets, there are no molecules to vibrate. There is no sound there.