Advertisements
Advertisements
प्रश्न
An electric appliance is rated at 1000 W, 250V. Calculate:
(i) The electrical energy consumed by the appliance in 12 hour.
(ii) The cost of energy consumed at Rs. 1.20 per kWh.
How long would this appliance take to use 1 kWh energy when operated at 250 V?
Advertisements
उत्तर
Given: P = 1000W, V = 250V, t = 12 hr
(i) Electrical energy consumed = `"Watt"/1000 xx "time" ("in hr.")`
`= 1000/1000 xx 12` = 12 kWh
(ii) Cost = 12 × 1.20 = Rs. 14.40
If it takes t hour to consume 1 kWh electric energy, then:
I = `(1000xx"t")/1000`
or t = 1 hr.
संबंधित प्रश्न
An electric kettle connected to the 230 V mains supply draws a current of 10 A. Calculate:
(a) the power of the kettle.
(b) the energy transferred in 1 minute.
Name two gases which are filled in filament type electric light bulbs.
1Kwh =`( 1 "volt "xx 1 am pere xx.............)/1000`
The coil of an electric bulb takes 40 watts to start glowing. If more than 40 W are supplied, 60% of the extra power is converted into light and the remaining into heat. The bulb consumes 100 W at 220 V. Find the percentage drop in the light intensity at a point if the supply voltage changes from 220 V to 200 V.
Tick(✓) the correct choice in the following:
In the circuit shown in the following fig, the e.m.f. of the cell is 4 volts, the current
flowing through the resistor is
An electric iron rated 750 W is operated for 2 hours/day. How much energy is consumed by the electric iron for 30 days?
Mention three uses of the carbon arc.
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?
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.
1 kWh = ____________
