Two lamps one rated 60 watt at 220v ad other 40w at 220v are connected in parallel to electric supply at 220v.
(a)Draw a circuit diagram to show the connections.
(b)Calculate the current drawn from the electric supply.
(c)Calculate the energy consumed by the two lamp together when they operate for one hour.
(a)
(b)
Using, I = P/V
Current drawn by 60 W lamp is, I = 220/60 = 3.67 A
Current drawn by 40 W lamp is, I/ = 220/40 = 5.5 A
So, the net current drawn by the combination is = 3.67 + 5.5 = 9.17 A
(c)
Net power of the combination = 60 + 40 = 100 W
So, the energy consumed in 1 h is = 100 × 1 × 60 × 60 J = 360000 J