Water in an electric kettle connected to a 220 V supply takes 5 minutes to reach it's boiling point. How long will it take if the supply voltage falls to 200 V?

An electric toaster draws current 8 A in a circuit with source of voltage 220 V. It is used for 2 h. Find the cost of operating the toaster if the cost of electrical energy is ₹ 4.50 per kWh.

An electric iron is rated 220 V, 2 kW. If the iron is used for 3h daily, find the cost of running it for 1 week if it costs ₹ 4.25 per kWh.

A geyser is rated '1500 W, 250 V'. This geyser is connected to 250 V mains. Calculate —

(i) the current drawn,

(ii) the energy consumed in 50 hours, and

(iii) the cost of energy consumed at ₹ 4.20 per kWh.