Advertisements
Advertisements
प्रश्न
उत्तर
APPEARS IN
संबंधित प्रश्न
State two factors on which the electrical energy consumed by an electrical appliance depends.
When a current of 4.0 A passes through a certain resistor for 10 minutes, 2.88 × 104 J of heat are produced. Calculate
the power of the resistor.
the voltage across the resistor.
Fig . shows the essent ial features of a battery operated bell. The hammer strikes the gong when the swi tch is closed . State and explain the effect of using the following material successively to form the core.
(a) Plastic
(b) Steel
(c) Copper
Water in an electric kettle connected to a 220 V supply took 5 minutes to reach its boiling point. How long will it take if the supply voltage falls to 200 V?
State three factors on which the heat produced in a metallic wire due to passage of current in it depends.
Two electric lamps each rating 100 W, 110 V are connected in series to a 220 V power supply and two other electric lamps each of marking 100 W, 220 V are connected in parallel to the same power supply. Will anyone of the two combinations give more light than the other? Give a reason for your answer.
What is the resistance of an appliance rated at V volt, P watt?
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.
What is the commercial unit of electrical energy? Represent it in terms of joules.
