Answer:
![4.35 \times 10^{14} Hz](https://tex.z-dn.net/?f=%204.35%20%5Ctimes%2010%5E%7B14%7D%20Hz)
Explanation:
The frequency of a light is inversely proportional to its wavelength. It is given by:
![f = \frac{v}{\lambda}](https://tex.z-dn.net/?f=f%20%3D%20%5Cfrac%7Bv%7D%7B%5Clambda%7D)
The speed of the red light, v = 3.0 × 10⁸ m/s
The wavelength of the red light, λ = 690 nm = 690 ×10⁻⁹ m
![f = \frac{3.0 \times 10^8 m/s}{690\times 10^{-9}m} = 4.35 \times 10^{14} Hz](https://tex.z-dn.net/?f=f%20%3D%20%5Cfrac%7B3.0%20%5Ctimes%2010%5E8%20m%2Fs%7D%7B690%5Ctimes%2010%5E%7B-9%7Dm%7D%20%3D%204.35%20%5Ctimes%2010%5E%7B14%7D%20Hz)
Thus, the frequency of red light emitted by neon sign having wavelength 690 nm is ![4.35 \times 10^{14} Hz](https://tex.z-dn.net/?f=%204.35%20%5Ctimes%2010%5E%7B14%7D%20Hz)
Answer:
The mercury in the barometer will go down as there is less air pressing down on the bulb of the barometer to push mercury up.
Explanation:
B)............... Have a good day, Have a nice day:)
Answer:
When the metal is dropped in the solution it turns blue to green because this forms iron sulphate solution and turns the metal copper
Iron sulphate + copper