Question

calculate the kinetic energy of an electron of mass 9x10^-31 when it moves with a velocity of 3x10^8 ms^-1

Answer 1

Answer:

λ=h/(2mK.E)

1/2

λ=6.626×10

−34

/(2×9.1×10

−31

×3×10

−25

)

1/2

=1.2×10

−7

m

Answer 2

Explanation:

K.E. => 21 mv 2

=> 21 ×9×10 −31 ×(10 7 ) 2

=> 4.5×10 −17 J (∵1.6×10 −19eV=1J)

=> 1.6×10 −194.5×10 −17 eV

=> 2.8125×10 ² eV

=>281.25 eV.