Q.1
The S.I. unit of power is
Q.2
A thermistor has
Q.3
Two bulbs of 500 W and 200 W rated at 250 V will have resistance ratio as
Q.4
For testing appliances, the wattage of test lamp should be
Q.5
Resistance of a material always decreases if
Q.6
The rating of a fuse wire is always expressed in
Q.7
The thickness of insulation provided on the conductor depends on
Q.8
If the efficiency of a machine is to be high, what should be low?
Q.9
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
Q.10
An instrument which detects electric current is known as
Q.11
All of the following are equivalent to watt except
Q.12
A rheostat differs from potentiometer in the respect that it
Q.13
The minimum charge on an ion is
Q.14
Current velocity through a copper conductor is
Q.15
For which of the following 'ampere second' could be the unit?
Q.16
Two resistances Rl and Ri are connected in series across the voltage source where Rl > Ri. The largest drop will be across
Q.17
A closed switch has a resistance of
Q.18
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:
Q.19
The resistivity of alloy manganin is
  • Nearly independent of temperature
  • Increases rapidly with increase in temperature
  • Decreases with increase in temperature
  • Increases rapidly with decrease in temperature
Q.20
In a Wheatstone bridge if the battery and galvanometer are interchanged then the deflection in galvanometer will
  • change in previous direction
  • not change
  • change in opposite direction
  • none of these.
Q.21
N a potentiometer ofwires, the balance point is obtained on the 7th wire. To shift the balance point to 9th wire, we should
  • decrease resistance in the main circuit.
  • increase resistance in the main circuit.
  • decrease resistance in series with the cell whose emf is to be measured.
  • increase resistance in series with the cell whose emf is to be determined.
Q.22
In parallel combination of n cells, we obtain
  • more voltage
  • more current
  • less voltage
  • less current
Q.23
Drift velocity vd varies with the intensity of electric field as per the relation
  • (vd ∝ E
  • vd ∝ 1/E
  • vd = constant
  • vd ∝ E²
Q.24
For measurement of potential difference, a potentiometer is preferred over voltmeter because
  • potentiometer is more sensitive than voltmeter.
  • the resistance of potentiometer is less than voltmeter.
  • potentiometer is cheaper than voltmeter.
  • potentiometer does not take current from the circuit.
Q.25
Who invented the light bulb
  • Thomas Edison
  • Joseph Swan
  • Hiram Maxim
  • All of above
Q.26
What is Coulombs Law
  • a law stating that like charges repel and opposite charges attract, with a force proportional to the product of the charges and inversely proportional to the square of the distance between them
  • a law stating that like charges repel and opposite charges attract, with a food proportional to the product of the charges and inversely proportional to the square of the distance between them
  • a law stating that like charges attract and opposite charges attract, with a force proportional to the product of the waste and inversely proportional to the square of the distance between them
  • a cafeteria stating that like charges repel and opposite charges attract, with a force proportional to the product of the charges and inversely proportional to the square of the distance between them
Q.27
What is a electro magnet
  • a hard rubber core made into a magnet by the passage of electric current through a coil surrounding it
  • a soft rubber core made into a magnet by the passage of electric current through a coil surrounding it
  • a hard metal core made into a magnet by the passage of electric current through a coil surrounding it
  • a soft metal core made into a magnet by the passage of electric current through a coil surrounding it
Q.28
What is the power of alight bulb withA running through it?
  • 0.15W
  • 6W
  • 60W
  • 6.67W
Q.29
Which of the following characteristics of electrons determines the current in a conductor?
  • Drift velocity alone
  • Thermal velocity alone
  • Both A and B
  • Neither A nor B
Q.30
A material in which electrons are not able to move easily
  • Circuit
  • Insulator
  • Resistance
  • Conductor
0 h : 0 m : 1 s