Question

How many bulbs of 81 ohm whould be needed when connected in parallel to draw current of 2A from 4V battery ?

Answer 1

Answer : Approximately 40 bulbs are required.

Explanation :

Let n number of identical bulbs(R) be connected in parallel.

Therefore effective resistance is R/n

Here the R/n = 81/n

Now,

V = IR

By substituting the values,

4 = 2 x 81/n

n = 40.5

Answer 2

Answer:

we know that v=IR

Explanation:

by substituting the values

v=I*R/n

4=2*81/n

n=40.5

thus it helps you.