Advertisements
Advertisements
प्रश्न
Why should the resistance of:
a voltmeter be very large?
Advertisements
उत्तर
A voltmeter should have a high resistance so that it can take only a negligible amount of current from the circuit.
APPEARS IN
संबंधित प्रश्न
Draw the electrical symbols of the following components and state its use:
Ammeter.
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
Fill in the folloing blank with suitable words:
A current is a flow of ............... .For this to happen there must be a ............... circuit.
A p.d. of 6 V is applied to two resistors of 3 Ω and 6 Ω connected in parallel. Calculate:
(a) the combined resistance
(b) the current flowing in the main circuit
(c) the current flowing in the 3 Ω resistor.
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?
Tick(✓) the correct choice in the following:
When the length of a conductor is doubled the resistance of the conductor
will
The circuit diagram (Fig.) shows a battery of e.m.f. 6 volts and internal
resistance of 0.8 Ω oonnected in series. Find the
(a) Current reoorded by the ammeter,
(b) P.d. across the terminals of the resistor B,
( c) Current passing through each of the resistors B, C and D, and
( d) P.d. across the terminals of the battery.
Complete the following:
1 kWh = _________ J
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.
State expression for Cells connected in series.
State the condition when it is advantageous to connect cells in series.
Which part of an electrical appliance is earthed?
State whether true or false. If false, correct the statement.
Current can produce magnetic field.
A current of 2A passing through the conductor produces 80 J of heat in 10 seconds. The resistance of the conductor is ______.
An ammeter is always placed in parallel with the circuit.
