Solve the following examples/ numerical problems.
Two tungsten bulbs of power of 50 w and 60 w work on 220 v potential difference . If they are connected in parallel, how much current will flow in the main conductor?

Answer

The total current flowing in the main conductor is 0.5A.

Explanation

Potential difference (V) = 220 V,
Power of bulb 1 `(P_(1))=50W`,
Power of bulb `1(P_(1))=50 W,`
Power of bulb `2(P_(2))=60W,`
To find: `" "` Total current (I)
`"Formulae: i. P = VI ii. I"=I_(1)+I_(2)`
Calculation: Since both the bulbs are connected in parallel, the potential difference will be same.
From formula (i),
`I_(1)=(P_(1))/(V)=(50)/(220)A,`
`I_(2)=(P_(2))/(V)=(60)/(220)A`
From formula (ii),
Total current is given by,
`I=(50)/(220)+(60)/(220)=(50+60)/(220)`
`therefore" "I=(110)/(220)=(1)/(2)`
`therefore" "I=0.5A`