Question

Calculate the kinetic energy of a moving electron which has a wavelength

of 4.8 pm. (m = 9.1 × 10-31kg, h = 6.6 × 10-34 Js).​

Answer 1

Answer:

Relationship between wavelength (

λ

) and momentum (

p

) is

λ

=

h

p

p

=

h

λ

=

6.63

×

10

−

34

J s

4.8

×

10

−

12

m

=

1.38

×

10

−

22

kg m/s

Now, find kinetic energy by relation

K.E

=

p

2

2

m

K.E

=

p

2

2

m

=

(

1.38

×

10

−

22

kg m/s

)

2

2

×

9.1

×

10

−

31

kg

=

1.05

×

10

−

14

Joule