Advertisements
Advertisements
प्रश्न
An electric kettle is rated 2.5 kW, 250 V. Find the cost of running the kettle for two hours at Rs. 5.40 per unit.
Advertisements
उत्तर
Given ,
Power of kettle , P = 2.5 kW
Voltage , V = 250 V
Time, t = 2 h
As , Energy , E = P × t
= 2.5 × 2 = 5 kWh
Cost per unit of energy = Rs 5.40
Cost for 5 kWh of energy = 5.40 × 5 = Rs 27
संबंधित प्रश्न
Draw a circuit diagram showing two electric lamps connected in parallel together with a cell and a switch that works both lamps. Mark an â’¶ on your diagram to show where an ammeter should be placed to measure the current.
Draw a schematic diagram of an electric circuit consisting of a battery of two cells each of 1.5 V, 5 Ω, 10 Ω and 15 Ω resistors and a plug key, all connected in series.
Distinguish between an open and a closed circuit.
Find the effective resistance in the following circuit diagrams (Fig.):

A current of 0.3 A is flowing through a branch of 6 Ω resistors in a junction as shown in fig. . Calculate the
(a) P.d. across the junction XY,
(b) Current flowing through 9Ω and 24Ω
( c) P.d. across 24 Ω resistor, and
( d) e.m.f. of the cell.

If the potential differences between two parts of a thundercloud is 10s V,
what is the amount of energy given up during the passage of 20 coulombs?
(a)2x10-7J
(b)200J
(c)Sx106 j
(d)2x 109J
(e)2x 1010 J
Match the following:
| 1. | 1 mA | a. | series |
| 2. | 1 pA | b. | ohmmeter |
| 3. | Ammeter | c. | 10-6 ampere |
| 4. | Electrical resistivity | d. | 10-3 ampere |
Define the following:
Conventional current
