An instrument which detects electric current is known as
An instrument which detects electric current is known as
If a wire conductor of 0.2 ohm resistance is doubled in length, its resistance becomes
If a wire conductor of 0.2 ohm resistance is doubled in length, its resistance becomes
Which is the best conductor of electricity?
Which is the best conductor of electricity?
A light bulb draws 300 mA when the voltage across it is 240 V. The resistance of the light bulb is
A light bulb draws 300 mA when the voltage across it is 240 V. The resistance of the light bulb is
The minimum charge on an ion is
The minimum charge on an ion is
Bulbs in street lighting are all connected in
Bulbs in street lighting are all connected in
Resistance of 220 V, 100 W lamp will be
Resistance of 220 V, 100 W lamp will be
Conductance is reciprocal of
Conductance is reciprocal of
What is the answer to this question? The resistance of a few meters of wire conductor in closed electrical circuit is
What is the answer to this question? The resistance of a few meters of wire conductor in closed electrical circuit is
In an electric kettle water boils in 10 m minutes. It is required to boil the boiler in 15 minutes, using same supply mains
In an electric kettle water boils in 10 m minutes. It is required to boil the boiler in 15 minutes, using same supply mains
Varistors are
Varistors are
Copper wire of certain length and resistance is drawn out to three times its length without change in volume, the new resistance of wire becomes
Copper wire of certain length and resistance is drawn out to three times its length without change in volume, the new resistance of wire becomes
One Newton meter is same as
One Newton meter is same as
Four wires of same material, the same cross-sectional area and the same length when connected in parallel give a resistance of 0.25 Q. If the same four wires are connected is series the effective resistance will be
Four wires of same material, the same cross-sectional area and the same length when connected in parallel give a resistance of 0.25 Q. If the same four wires are connected is series the effective resistance will be
When one leg of parallel circuit is opened out the total current will
When one leg of parallel circuit is opened out the total current will
Temperature coefficient of resistance is expressed in terms of
Temperature coefficient of resistance is expressed in terms of
A rheostat differs from potentiometer in the respect that it
A rheostat differs from potentiometer in the respect that it
Nichrome wire is an alloy of
Nichrome wire is an alloy of
The resistance of a copper wire 200 m long is 21 ω. If its thickness (diameter) is 0.44 mm, its specific resistance is around
The resistance of a copper wire 200 m long is 21 ω. If its thickness (diameter) is 0.44 mm, its specific resistance is around
The number of electrons in the outer most orbit of carbon atom is
The number of electrons in the outer most orbit of carbon atom is
You have to replace 1500 Q resistor in radio. You have no 1500 Q resistor but have several 1000 Q ones which you would connect
You have to replace 1500 Q resistor in radio. You have no 1500 Q resistor but have several 1000 Q ones which you would connect
A 3 Q resistor having 2 A current will dissipate the power of
A 3 Q resistor having 2 A current will dissipate the power of
Which method can be used for absolute measurement of resistances?
Which method can be used for absolute measurement of resistances?
The condition for the validity under Ohm’s law is that
The condition for the validity under Ohm’s law is that
If a parallel circuit is opened in the main line, the current
If a parallel circuit is opened in the main line, the current
Insulating materials have the function of
Insulating materials have the function of
What will be energy used by the battery if the battery has to drive 6.28 x 10¹⁸ electrons with potential difference of 20 V across the terminal ?
What will be energy used by the battery if the battery has to drive 6.28 x 10¹⁸ electrons with potential difference of 20 V across the terminal ?
Out of the following which is an insulating material?
Out of the following which is an insulating material?
Two resistances Rl and Ri are connected in series across the voltage source where Rl > Ri. The largest drop will be across
Two resistances Rl and Ri are connected in series across the voltage source where Rl > Ri. The largest drop will be across
Out of the following which is not a poor conductor?
Out of the following which is not a poor conductor?
Ohm’s law is not applicable to
Ohm’s law is not applicable to
A substance whose molecules consist of dissimilar atoms is called
A substance whose molecules consist of dissimilar atoms is called
Resistance of a tungsten lamp as applied voltage increases
Resistance of a tungsten lamp as applied voltage increases
A closed switch has a resistance of
A closed switch has a resistance of
A current of 16 amperes divides between two branches in parallel of resistances 8 ohms and 12 ohms respectively. The current in each branch is
A current of 16 amperes divides between two branches in parallel of resistances 8 ohms and 12 ohms respectively. The current in each branch is
Electric current passing through the circuit produces
Electric current passing through the circuit produces
Two resistors are said to be connected in series when
Two resistors are said to be connected in series when
International ohm is defined in terms of the resistance of
International ohm is defined in terms of the resistance of
Heat in a conductor is produced on the passage of electric current due to
Heat in a conductor is produced on the passage of electric current due to
Which of the following can have negative temperature coefficient?
Which of the following can have negative temperature coefficient?
When electric current passes through a bucket full of water, lot of bubbling is observed. This suggests that the type of supply is
When electric current passes through a bucket full of water, lot of bubbling is observed. This suggests that the type of supply is
The rating of a fuse wire is always expressed in
The rating of a fuse wire is always expressed in
Three identical resistors are first connected in parallel and then in series. The resultant resistance of the first combination to the second will be
Three identical resistors are first connected in parallel and then in series. The resultant resistance of the first combination to the second will be
When electric current passes through a metallic conductor, its temperature rises. This is due to
When electric current passes through a metallic conductor, its temperature rises. This is due to
The weight of an aluminium conductor as compared to a copper conductor of identical cross-section, for the same electrical resistance, is
The weight of an aluminium conductor as compared to a copper conductor of identical cross-section, for the same electrical resistance, is
A thermistor has
A thermistor has
The condition for the validity under Ohm's law is that
The condition for the validity under Ohm's law is that
For testing appliances, the wattage of test lamp should be
For testing appliances, the wattage of test lamp should be
When a voltage of one volt is applied, a circuit allows one micro ampere current to flow through it. The conductance of the circuit is
When a voltage of one volt is applied, a circuit allows one micro ampere current to flow through it. The conductance of the circuit is
The resistance of a conductor varies inversely as
The resistance of a conductor varies inversely as
In a circuit a 33 Q resistor carries a current of 2 A. The voltage across the resistor is
In a circuit a 33 Q resistor carries a current of 2 A. The voltage across the resistor is
In a series circuit with unequal resistances
In a series circuit with unequal resistances
The thickness of insulation provided on the conductor depends on
The thickness of insulation provided on the conductor depends on
Which of the following materials has the least resistivity ?
Which of the following materials has the least resistivity ?
The hot resistance of the bulb's filament is higher than its cold resistance because the temperature coefficient of the filament is
The hot resistance of the bulb's filament is higher than its cold resistance because the temperature coefficient of the filament is
Two lamps 100 W and 40 W are connected in series across 230 V (alternating). Which of the following statement is correct?
Two lamps 100 W and 40 W are connected in series across 230 V (alternating). Which of the following statement is correct?
When resistance element of a heater fuses and then we reconnect it after removing a portion of it, the power of the heater will
When resistance element of a heater fuses and then we reconnect it after removing a portion of it, the power of the heater will
Three 6 ohm resistors are connected to form a triangle. What is the resistance between any two corners?
Three 6 ohm resistors are connected to form a triangle. What is the resistance between any two corners?
Conductance: mho ::
Conductance: mho ::
A nichrome wire used as a heater coil has the resistance of 2 £2/m. For a heater of 1 kW at 200 V, the length of wire required will be
A nichrome wire used as a heater coil has the resistance of 2 £2/m. For a heater of 1 kW at 200 V, the length of wire required will be
Two copper conductors have equal length. The cross-sectional area of one conductor is four times that of the other. If the conductor having smaller cross-sectional area has a resistance of 40 ohms the resistance of other conductor will be
Two copper conductors have equal length. The cross-sectional area of one conductor is four times that of the other. If the conductor having smaller cross-sectional area has a resistance of 40 ohms the resistance of other conductor will be
Which of the following quantities remain the same in all parts of a series circuit?
Which of the following quantities remain the same in all parts of a series circuit?
Which of the following statement is correct?
Which of the following statement is correct?
Are the materials having electrical conductivity much less than most of the metals but much greater than that of typical insulators.
Are the materials having electrical conductivity much less than most of the metals but much greater than that of typical insulators.
The property of a conductor due to which it passes current is called
The property of a conductor due to which it passes current is called
Three 60 W bulbs are in parallel across the 60 V power line. If one bulb burns open
Three 60 W bulbs are in parallel across the 60 V power line. If one bulb burns open
The filament of an electric bulb is made of
The filament of an electric bulb is made of
Two bulbs of 500 W and 200 W rated at 250 V will have resistance ratio as
Two bulbs of 500 W and 200 W rated at 250 V will have resistance ratio as
Which of the following materials has a negative temperature coefficient of resistance?
Which of the following materials has a negative temperature coefficient of resistance?
It becomes more difficult to remove
It becomes more difficult to remove
Which of the following statement is true both for a series and a parallel D.C. circuit?
Which of the following statement is true both for a series and a parallel D.C. circuit?
Which of the following statement is true?
Which of the following statement is true?
An open resistor, when checked with an ohmmeter reads
An open resistor, when checked with an ohmmeter reads
In a lamp load when more than one lamp are switched on the total resistance of the load
In a lamp load when more than one lamp are switched on the total resistance of the load
Which of the following material has nearly zero temperature coefficient of resistance?
Which of the following material has nearly zero temperature coefficient of resistance?
The S.I. unit of power is
The S.I. unit of power is
All good conductors have high
All good conductors have high
The substances which have a large number of free electrons and offer a low resistance are called
The substances which have a large number of free electrons and offer a low resistance are called
If I, R and t are the current, resistance and time respectively, then according to Joule’s law heat produced will be proportional to
If I, R and t are the current, resistance and time respectively, then according to Joule’s law heat produced will be proportional to
A field of force can exist only between
A field of force can exist only between
In the case of direct current
In the case of direct current
Which one of the following does not have negative temperature coefficient?
Which one of the following does not have negative temperature coefficient?
The four bulbs of 40 W each are connected in series swift a battery across them, which of the following statement is true?
The four bulbs of 40 W each are connected in series swift a battery across them, which of the following statement is true?
For which of the following 'ampere second' could be the unit?
For which of the following 'ampere second' could be the unit?
The ratio of mass of proton to that of electron is nearly
The ratio of mass of proton to that of electron is nearly
Whether circuit may be AC. or D.C. one, following is most effective in reducing the magnitude of the current.
Whether circuit may be AC. or D.C. one, following is most effective in reducing the magnitude of the current.
With three resistances connected in parallel, if each dissipates 20 W the total power supplied by the voltage source equals
With three resistances connected in parallel, if each dissipates 20 W the total power supplied by the voltage source equals
The resistance of a parallel circuit consisting of two branches is 12 ohms. If the resistance of one branch is 18 ohms, what is the resistance of the other?
The resistance of a parallel circuit consisting of two branches is 12 ohms. If the resistance of one branch is 18 ohms, what is the resistance of the other?
An electric filament bulb can be worked from
An electric filament bulb can be worked from
With rise in temperature the resistance of pure metals
With rise in temperature the resistance of pure metals
Voltage dependent resistors are usually made from
Voltage dependent resistors are usually made from
Voltage dependent resistors are used
Voltage dependent resistors are used
Switching of a lamp in house produces noise in the radio. This is because switching operation produces
Switching of a lamp in house produces noise in the radio. This is because switching operation produces
Three resistances of 10 ohms, 15 ohms and 30 ohms are connected in parallel.
The total resistance of the combination is
Three resistances of 10 ohms, 15 ohms and 30 ohms are connected in parallel.
The total resistance of the combination is
A resistance having rating 10 ohms, 10 W is likely to be a
A resistance having rating 10 ohms, 10 W is likely to be a
Resistance of carbon filament lamp as the applied voltage increases.
Resistance of carbon filament lamp as the applied voltage increases.
All of the following are equivalent to watt except
All of the following are equivalent to watt except
Sparking occurs when a load is switched off because the circuit has high
Sparking occurs when a load is switched off because the circuit has high
Electric pressure is also called
Electric pressure is also called
A 40 W bulb is connected in series with a room heater. If now 40 W bulb is replaced by 100 W bulb, the heater output will:
A 40 W bulb is connected in series with a room heater. If now 40 W bulb is replaced by 100 W bulb, the heater output will:
A glass rod when rubbed with silk cloth is charged because
A glass rod when rubbed with silk cloth is charged because
The insulation on a current carrying conductor is provided
The insulation on a current carrying conductor is provided
If the efficiency of a machine is to be high, what should be low?
If the efficiency of a machine is to be high, what should be low?
When current flows through heater coil it glows but supply wiring does not glow because
When current flows through heater coil it glows but supply wiring does not glow because
Ohm's law is not applicable to
Ohm's law is not applicable to
With rise in temperature the resistance of semiconductors
With rise in temperature the resistance of semiconductors
Current velocity through a copper conductor is
Current velocity through a copper conductor is
Resistance of a material always decreases if
Resistance of a material always decreases if
