Question

Find the number of electrons emitted per second by a 24w source

Answer 1

The number of electrons emitted per second by a 24w source will be    6.25 x 10¹⁷

Explanation :

Assuming a source voltage of 240 V,

Current = power/ voltage

=> Current = 24/240 = 0.1 A

Since

current = charge/time

=> charge = current x time = 0.1 x 1 = 0.1 Coulomb

Charge of 1 electron = 1.6 x 10⁻¹⁹ coulomb

=> 1 coulomb = 1/(1.6 x 10⁻¹⁹) = 0.625 x 10¹⁹ electrons

=> 0.1 coulomb = 0.1 x  0.625 x 10¹⁹

= 0.0625 x 10¹⁹

= 6.25 x 10¹⁷ electrons

Hence the number of electrons emitted per second by a 24w source will be  6.25 x 10¹⁷