Question

Find the energy of electron if the wave length
of light is 6500A
A 3x 10-20j
B 3 x 10-19j
C 6x 10 18J
D 30x 10-19 J​

Answer 1

Answer:

Explanation:

Given:  

mass of an electron =  9.1×10  

−31

kg

kinetic energy = 3.0×10  

−25

 J

h = 6.6×10  

−34

 Js

By using de- Broglie equation :

λ=  

mv

h

​

 =  

p

h

​

  ,where  h = Planck's constant, p= momentum

as P =  

2×E×m

​

 , by subtituting the value of p we get,

wavelength =  

2×E×m

​

 

h

​

         (E= kinetic energy )

wavelength =  

2×3×10  

−25

×9.1×10  

−31