Advertisements
Advertisements
प्रश्न
Consider the circuit given below:
(a) In which circuit are the lamps dimmest?
(b) In which circuit or circuits are the lamps of equal brightness to the lamps in circuit (i)?
(c) Which circuit gives out the maximum light?
Advertisements
उत्तर
(a) The lamps will be the dimmest in the series circuit (ii) because the voltage will be divided between the two lamps.
(b) In circuit (iii), the lamps will be as bright as in circuit (i) because circuit (iii) is a parallel arrangement. In a parallel arrangement, the voltage remains the same.
(c) Circuit (iii) will give the maximum light as circuit (iii) has a parallel arrangement. A parallel arrangement offers less resistance and thus circuit (iii) will give more light.
APPEARS IN
संबंधित प्रश्न
1 A = _________ mA
- 102
- 103
- 10-3
- 10-6
Define the unit of current.
<p> Define the unit of electric current (or Define ampere).
A 5 V battery is connected to two 20 Ω resistors which are joined together in series.
(a) Draw a circuit diagram to represent this. Add an arrow to indicate the direction of conventional current flow in the circuit.
(b) What is the effective resistance of the two resistors?
(c) Calculate the current that flows from the battery?
(d) What is the p.d. across each resistor?
The lamps in a house hold circuit are connected in parallel because:
(a) this way they required less current
(b) if one lamp fails the others remain lit
(c) this way they require less power
(d) if one lamp fails the other also fail
A wire of uniform thickness with a resistance of 27Ω is cut into three equal pieces and they are joined in parallel. Find the equivalent resistance of the parallel combination.
Two resistors of 2.0 Ω and 3.0 Ω are connected (a) in series (b) in parallel, with a battery of 6.0 V and negligible internal resistance. For each case draw a circuit diagram and calculate the current through the battery.
A battery of e.m.f. 15 V and internal resistance 3 ohm is connected to two resistors of resistance 3 ohm and 6 ohm in series. Find:
(i) The current through the battery,
(ii) The p.d. between the terminals of the battery.
Calculate the amount of energy transferred by a 10 A electric current flowing through a resistor of 5 o for 15 minutes.
If a fuse contains a 5 A fuse wire and the voltage is 240 V, what is the maximum power (wattage) which may be taken from the circuit?
60 joules of heat was dissipated in a resistor when 20 C flowed for 5 s. Calculate:
(a) P.d. across the resistor,
(b) Resistance of the resistor, and
(c) Average power dissipated in the resistor.
Fig. shows a 3 pin plug with the cover removed. The electric cable
connected to the plug contains 3 wires with colour coded insulation namely brown, blue and green.
- Identify each of the colour coded wires by stating to which of the
terminals A, B or C in the diagram they should be connected. - Identify the terminal through which no current passes in normal
circumstances. - What is the purpose of the earthed wire connected to an electric
appliance like an electric heater? Describe how it works.
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
A bulb of 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.
Which part of an electrical appliance is earthed?
Water : pipe :: Electric current : ______.
Conventionally, the direction of the current is taken as:
The magnitude of Alternating Current (AC):
