List the names of three electrical gadgets used in your house. Write their power, voltage rating and approximate time for which each one is used in a day. Hence find the electrical energy consumed by each in a month of 30 days.

A bulb of power 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.

If an electric iron of 1200 W is used for 30 minutes everyday, find electric energy consumed in the month of Aprill.

In a house there are four bulbs each of 50W and 5 fans each of 60W. If they are used at the rate of 6 hours a day. The electrical energy consumed in a month of 30 days is

A 2k W heater used for 1 h every day consumes the following electrical energy in 30 days

An electric bulb of 60 W is used for 6 h per day. Calculate the units of energy consumed in one day by the bulb.

A 1 k W heater is meant to operate at 200 V . (a) What is the resistance? (b) How much power will it consume if the line voltage drops to 100 V ? ( c ) How many units of electrical energy will it consume in a month ( of 30 days) if it operates 10 h daily at the specified voltage ( 200 V) ?

The teachers of Geeta's school took the students on a study tirp to a power generating station, loactad nearly 200km away form the city.The teacher explained that electrical energy is transmitted over such a long distance to their city, in the form of alternating current (ac) raised to a high voltage. At the receiving end is the city, the voltage is reduced to operate the devices. As a result, the power loss is reduced. Geeta listened to the teacher and asked question about how the ac is converted to a higher or lower voltage. (a) Name th device used to change the alternating to a higher or lower value. State one cause for power dissipation in this device. (b) Explain with an example, how power loss is reduced if the energy is transmitted over long distance as an alternating current rather than a direct current, (c) Write two values each shown by the teachers and Geeta.

State one important advantage and disadvantage each of using nuclear energy for producing electricity.

An L-C-R series circuit with L = 0.120 H, R = 240 a , and C = 7.30muF carries an rms current of 0.450 A with a frequency of 400 Hz . (a) What are the phase angle and power factor for this circuit? (b) What is the impedance of the circuit? (c) What is the rms voltage of the source? (d) What average power is delivered by the source? (e) What is the average rate at which electrical energy is converted to thermal energy in the resistor? (f) What is the average rate at which electrical energy is dissipated ( converted to other forms) in the capacitor? (g) In the inductor ?

Draw the diagram a of galvanic cell involving following reactions : Zn+Cu^(+) to Zn^(2+) +Cu and answer the following questions: (i) Label the cathode and anode (ii) How does the e.m.f. of the cell changes with the decrease in the concentration of Cu^(2+) ions ? (iii) What is the function of salt bridge in it? (iv) Name the salt to be used in salt bridge. (v) Write the reactions occurring at each electrode. (vi) In which direction the electrons would flow in the external circuit? (vii) How electrical neutrality is maintained in both the half cells?