Lithium-7 is by far the most-common isotope, making up about 92.5 percent of all natural lithium. A lithium-7 atom contains three protons, four neutrons, and three electrons.
Answer:
Explanation:
Suppose initially the plane was horizontal and light was reflected back at some angle θ from the normal .
Now the reflecting surface is twisted so that is becomes inclined at angle alpha .
The reflected light will be deviated from its original direction by angle
2 x alpha .
Similarly when the reflecting surface is further twisted so that it becomes inclined at angle beta then again the reflected beam will deviated by angle
2 x beta
Hence angle between these two reflected beam
= 2 beta - 2 alpha
= 2 ( β - α )
So, angular separation between the rays reflected from the two surfaces
= 2 ( β - α ) .
1. Define Newtons second law of motion (this will help put things into perspective)
2.Get the mass of the object (in this case 75 kg)
3.The net force acting on the object...find it (in this case 500 N)
4.Change the equation to F=ma (500=75a)
5.Divide both sides by 75 and that is the acceleration.
Answer:
The frequency of the photon is 
.
Explanation:
Given that,
Energy 
We need to calculate the energy
Using relation of energy
Where, 
= energy spacing
Put the value of h into the formula
Hence, The frequency of the photon is .
