Question
Physics Question on Electric Current
The number of electrons flowing per second in the filament of a 110 W bulb operating at 220 V is: (Given e=1.6×10−19 C)
A
31.25×1017
B
6.25×1018
C
6.25×1017
D
1.25×1019
Answer
31.25×1017
Explanation
Solution
Given:
Power (P)=V⋅I
110=220×I
I=0.5A
Now, we know:
I=tn⋅e
Substitute the values:
0.5=tn×(1.6×10−19)
Rearrange to solve for n:
tn=1.6×10−190.5
tn=31.25×1017