Advertisements
Advertisements
प्रश्न
Fill in the folloing blank with suitable words:
A current is a flow of ............... .For this to happen there must be a ............... circuit.
Advertisements
उत्तर
A current is a flow of electrons. For this to happen, there must be a closed circuit.
APPEARS IN
संबंधित प्रश्न
In which direction do electrons flow?
Compare how an ammeter and a voltmeter are connected in a circuit.
Why should the resistance of:
an ammeter be very small?
The p.d. across a 3 Ω resistor is 6 V. The current flowing in the resistor will be:
(a) `1/2A`
(b) 1 A
(c) 2 A
(d) 6 A
Three resistors are connected as shown in the diagram.
Through the resistor 5 ohm, a current of 1 ampere is flowing.
(i) What is the current through the other two resistors?
(ii) What is the p.d. across AB and across AC?
(iii) What is the total resistance
The figure given below shows an electric circuit in which current flows from a 6 V battery through two resistors.
- Are the resistors connected in series with each other or in parallel?
- For each resistors, state the p.d. across it.
- The current flowing from the battery is shared between the two resistors. Which resistor will have bigger share of the current?
- Calculate the effective resistance of the two resistors.
- Calculate the current that flows from the battery.
(a) With the help of a circuit diagram, obtain the relation for the equivalent resistance of two resistances connected in parallel.
(b) In the circuit diagram shown below, find:
(i) Total resistance.
(ii) Current shown by the ammeter A

Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a parallel circuit to an identical power supply line.
(a) Which circuit would have the highest voltage across each bulb?
The rating of a fuse connected in the lighting circuit is:
(a) 15 A (b) 5 A (c) 10 A (d) Zero
Match the pairs.
| ‘A’ Group | ‘B’ Group |
| 1. Free electrons | a. V/R |
| 2. Current | b. Increases the resistance in the circuit |
| 3. Resistivity | c. Weakly attached |
| 4. Resistances in series | d. VA/LI |
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?
Find the effective resistance in the following circuit diagrams (Fig.):

Name the principle on which a transformer works.
Answer the following question.
An electric lamp of resistance 20 Ω and a conductor of resistance 4 0 are connected to a 6 V battery as shown in the circuit. Calculate: 
(a) the total resistance of the circuit,
(b) the current through the circuit,
(c) the potential difference across the (i) electric lamp and (ii) conductor, and
(d) power of the lamp.
Kilowatt hour is the unit of
What is the SI unit for the current?
