Advertisements
Advertisements
प्रश्न
State two factors on which the electrical energy consumed by an electrical appliance depends.
Advertisements
उत्तर
Two factors on which electrical energy consumed by an electrical appliance depends on are:
(1) power
(2) time
APPEARS IN
संबंधित प्रश्न
Define Electric power.
What determines the rate at which energy is delivered by a current?
1 kWh = ________ J
Name the quantity whose unit is (i) kilowatt, and (ii) kilowatt-hour.
The unit for expressing electric power is:
(a) volt
(b) joule
(c) coulomb
(d) watt
An electric kettle for use on a 230 V supply is rated 3000 W. For safe working, the cable connected to it should be able to carry at least:
(a) 2 A
(b) 5 A
(c) 10 A
(d) 15 A
An electric heater of resistance 8 Ω takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater.
Write an expression for the electrical power spent in flow of current through a conductor in terms of
(a) Resistance and potential difference, (b) current and resistance.
A current of 2 A is passed through a coil of resistance 75Ω for 2 minutes. (a) How much heat energy is produced? (b) How much charge is passed through the resistance?
Water in an electric kettle connected to a 220 V supply took 5 minutes to reach its boiling point. How long would it have taken if the supply voltage had fallen to 200 V?
A simple electric circuit has 24 V battery and a resistor of 60 Ω. What will be the current in the circuit? The resistance of the connecting wires is negligible.
Which cable, one rated 15A and the other rated 5A will be thicker? Give a reason.
Name a metal that is used as an electron emitter. Give one reason for using this metal.
State other bigger units of electric power and express them in watt.
An electric kettle is rated 3kW, 250V. What should be the current capacity of the fuse with it?
An electric lamp A of 40 W and another electric lamp B of 100 W are connected to 220 V supply. Calculate the ratio of their filament resistances?
A house is provided with 15 bulbs of 40W, 5 bulbs of 100W, 5 fans of 80 W, and one heater of 1.0 kW. Each day bulbs are used for 4h, fans for lOh, and heater for 2h. The voltage of mains is 220 V. Calculate:
(i) Maximum power of the circuit in the house,
(ii) maximum current capacity of the main fuse in the house,
(iii) the electrical energy consumed in a week,
(iv) cost of electricity consumed at 1.25 Rs. per kWh.
