Three bulbs,each having a resistance of `180(Omega)`are connected in parallel to an ideal battery of emf60V. Find the current delivered by the battery when (a)all the bulbs are switched on,(b)two of the bulbs are switched on and (c )only one bulb is switched on.

Explanation

(a)` R_eff = 180/3 = 60 Omega `
` i= 60/60= 1A `
` (b) R_eff = 180/2 = 90 Omega `
`i=60/90 = 0.67 A `
` (c) R_eff = 180 Omega. `
` i=60/180 = 0.33A `.