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प्रश्न
State other bigger units of electric power and express them in watt.
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उत्तर
The other bigger units of power commonly used are:
1 kilowatt = 1000 watt
1 Horse power (H.P.) = 746 watt
Megawatt = 106 watt
संबंधित प्रश्न
If a bulb of 60W is connected across a source of 220V, find the current drawn by it.
State two factors on which the electrical energy consumed by an electrical appliance depends.
A bulb is rated as 250 V; 0.4 A. Find its : (i) power, and (ii) resistance.
The table below shows the current in three different electrical appliances when connected to the 240 V mains supply:
| Appliance | Current |
| Kettle | 8.5 A |
| Lamp | 0.4 A |
| toaster | 4.8 A |
- Which appliance has the greatest electrical resistance? How does the data show this?
- The lamp is connected to the main supply by using a thin, twin-cored cable consisting of live and natural wires. State two reasons why this cable should not be used for connecting the kettle to the mains supply.
- Calculate the power rating of the kettle when it is operated from the 240 V mains supply.
- A main takes the kettle abroad where the mains supply is 120 V. What is the current is the kettle when it is operated from the 120 V supply?
Point out two main disadvantages of ‘Tree System’.
How does the heat produced by die passage of current in a metallic wire depend on the resistance of the wire.
With reference to the diagram shown below calculate:
(i) The equivalent resistance between P and Q.
(ii) The reading of ammeter.
(iii) The electrical power between P and Q.
A family uses a light bulb of 100W, a fan of 100W, and a heater of 1000W, each for 8 hours a day. If the cost of electricity is Rs. 2 per unit, what is the expenditure to the family per day, on electricity?
Two bulbs are rated: bulb A 100W, 120 V bulb B 10W, 120 V. If both are connected across a 120V supply, which bulb will consume more energy, When in series? Also calculate the current through each bulb in above cases.
An electrical appliance is rated 1500 W, 250 V. This appliance is connected to 250 V mains. Calculate:
(i) the current drawn,
(ii) the electrical energy consumed in 60 hours,
(iii) the cost of electrical energy consumed at Rs. 2.50 per kWh.
