Question

a wire contains a steady current of 2A. the number of electrons that pass a cross section 2s is:

Answer 1

current i = 2 A
time t= 2 s
charge pass a crosssection q = it = 4 C
= [ 4C / ( 1.6 * 10^-19 C ) ] e
where e = charge of electron = 1.6 * 10^ -19 C
So, q = 2.5*10^19 * e
Therefore No.of electons N = q / e
= 2.5 * 10^19

Answer 2

chagre passing in 2 sec = 4C

charge of each electron = 1.6 * 10^-19
hence no.of electrons = 4/1.6 * 10^-19

= 2.5 *10^19

Answer 3

Q=it Q=2×2 Q=4C

Answer 4

Q=it Q=2×2 Q=4C