Advertisements
Advertisements
प्रश्न
Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply of the energy supplied in kWh to the three heaters in 5 hours.
Advertisements
उत्तर
Given ,
Power , P = 250 W
Voltage , V = 100 V
Time for which energy is supplied , t = 5 h
As , Energy E = P × t
E = 250 × 5 = 1250 Wh
or E = 1.25 kWh
Energy for three heaters = 3 × 1.25 = 3.75 kWh
संबंधित प्रश्न
The work done in moving a unit charge across two points in an electric circuit is a measure of:
(a) current
(b) potential difference
(c) resistance
(d) power
If 20 C of charge pass a point in a circuit in 1 s, what current is flowing?
Which statement/statement is/are correct?
1. An ammeter is connected in series in a circuit and a voltmeter is connected in parallel.
2. An ammeter has a high resistance.
3. A voltmeter has a low resistance.
(a) 1, 2, 3
(b) 1, 2
(c) 2, 3
(d) 1
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.
Calculate the effective resistance between the points A and B in the network shown below in Figure 8.45

A charge of 80 C flows in a conductor for 2 minutes.
(a) Calculate the current flowing through the conductor.
(b) If the current through a heater is 4 A what charge must be passing in 8 seconds?
Two cells each having an e.m.f. of 2 V and an internal resistance of 2Ω are
connected (a) In series, and ( b) In para 1le l as shown in fig. . What is the
current flowing through the cir cu it in each_ case?

An auto lamp is joined to a battery of e.m.f. 4 V and internal resistance 2.5Ω. A steady current of 0.5 A flows through the circuit. Calculate the
(a) Total energy provided by battery in 10 minutes,
(b) Heat dissipated in the bulb in 10 minutes.
Electrical power P is given by the expression P = (Q × V) ÷ time
(a) What do the symbols Q and V represent?
(b) Express the power P in terms of current and resistance explaining the meanings of symbols used there in.
What is the speed of electric current?
