The first ariplanr was made December 17, 1903
The use of force to move an object is called work. This only applies if the object moves.
Answer:
![f=6.97\times 10^{14}\ Hz](https://tex.z-dn.net/?f=f%3D6.97%5Ctimes%2010%5E%7B14%7D%5C%20Hz)
Explanation:
Given that,
Wavelength, ![\lambda=430\ nm=430\times 10^{-9}\ m](https://tex.z-dn.net/?f=%5Clambda%3D430%5C%20nm%3D430%5Ctimes%2010%5E%7B-9%7D%5C%20m)
We need to find the frequency of the violet light.
We know that the relation between frequency and wavelength is given by :
![f=\dfrac{c}{\lambda}\\\\f=\dfrac{3\times 10^8}{430\times 10^{-9}}\\\\f=6.97\times 10^{14}\ Hz](https://tex.z-dn.net/?f=f%3D%5Cdfrac%7Bc%7D%7B%5Clambda%7D%5C%5C%5C%5Cf%3D%5Cdfrac%7B3%5Ctimes%2010%5E8%7D%7B430%5Ctimes%2010%5E%7B-9%7D%7D%5C%5C%5C%5Cf%3D6.97%5Ctimes%2010%5E%7B14%7D%5C%20Hz)
So, the frequency of violet light is
.
Answer:
0.002833 sec
Explanation:
Speed of light in vacuum is ![3\times 10^{8}m/sec](https://tex.z-dn.net/?f=3%5Ctimes%2010%5E%7B8%7Dm%2Fsec)
Given distance = 850 km = 850×1000=850000 m
We have to calculate the time that light take to travel the distance 850 km
Time ![T=\frac{distance }{speed}=\frac{850000}{3\times 10^8}=2.833\times 10^{-3}sec](https://tex.z-dn.net/?f=T%3D%5Cfrac%7Bdistance%20%7D%7Bspeed%7D%3D%5Cfrac%7B850000%7D%7B3%5Ctimes%2010%5E8%7D%3D2.833%5Ctimes%2010%5E%7B-3%7Dsec)
So the time taken by light to travel 850 km is 0.002833 sec