Calculate the cost of heating 4.6kg of water for `25^(@)C` to the boiling point, assuming that no energy is wasted. Electrical energy costs 25 paisa per kWh.

A electric kettle ( rated accurately at 2.5 kW ) is used to heat 3 kg of water from 15^(@)C to boiling point . It takes 9.5 min . Then the amount of heat that has been lost is

A refrigerator having a power rating of 350W operates for 10 hours a day. Calculate the cost of electrical energy to operate if for a month of 30 days. The rate of electrical energy is Rs. 340 per kWh.

(a) Calculate the heat that must be supplied to raise the temperature of 2 kg of water from 25^(@) C to its boiling point at atmospheric pressure.The average specific heat of water in the range 25 - 100^(@)C is 4.184 J K^(-1) g^(-1) . (b)How long will a 2 kW heater take to supply this energy?

Calculate the amount of heat produced per second (in calories ) when a bulb of 100 W ,220 W glows, assuming that only 20 % of electric energy is connected into light J = 4.2 J cal^(-1)

100 capacitors each having a capacity of 10 muF are connected in parallel and are charged by a potential difference of 100 kV . The energy stored in the capacitors and the cost of charging them, if electrical energy costs 108 paise per kWh , will be

How much heat energy is gained when 5 kg of water at 20^(@)C is brought to its boiling point (Specific heat of water = 4.2 kj kg c)

The heat produced on complete combustion of 20 g of a fuel could raise the temperature of 1.5 kg of water form 25^(@)C to 75^(@)C . Calculate the calorific value of the fuel if the specific heat capacity of water is 4.2 J g^(-1).^(@)C^(-1) . Assume that the heat absorbed by the container is negligible.

A copper electric kettle weighing 1000 g contains 900g of water at 20^(@)C it takes 12 minutes to raise the temperature to 100^(@)C . If electric energy is supplied at 210V, calculate the strength of the current, assuming that 10% heat is wasted. Specific heat of copper is 0.1.

A copper electric kettle weighing 1000 g contains 900g of water at 20^(@)C it takes 12 minutes to raise the temperature to 100^(@)C . If electric energy is supplied at 210V, calculate the strength of the current, assuming that 10% heat is wasted. Specific heat of copper is 0.1.