An electric tungsten bulb is connected into a home circuit. The home electric supply runs at 220 V potential difference. When switched on, a current of 0.45 A flows thorugh the bulb. What must be power (wattage) of the bulb? If it is kept on for 10 hours, how many units of electricity will be consumed?

Answer

Power of the bulb is 99 watt and 0.99 units of electricity will be consumed in 10 hours.

Explanation

`"Given : Potential difference (V) = 220 V,"`
`" Electric current (I) = 0.45 A"`
`" Time (t) = 10 hours"`
`"To find: Power (P), units of electricity consumed"`
`"Formula: P = VI"`
`"Calculation: From formula,"`
`P=220xx0.45=99W`
In 10 hours, the power consumed is `99xx10=990Wh=0.99kWh`