ECAT Pre Engineering Physics Chapter 12 MCQ Test With Answer

If the resistance of 2 ohm and 4 ohm are connected in parallel, the equivalent resistance will be

• 6 ohm A
• 4 ohm B
• zero ohm C
• 1.33 ohm D

The colour sequence in a carbon resistor in red, brown, orange and silver. The resistance of the resistor is

• 21 x 10³+ 10% A
• 23 x 10¹+ 10% B
• 21 x 10³+ 5% C
• 12 x 10³+ 5% D

Electric generators which convert mechanical energy into

• solar energy A
• thermal energy B
• kinetic energy C
• electrical energy D

Resistance of a conductor depends upon

• the quantity of current passing through it A
• the voltage applied between its end B
• its dimensions, physical state and nature of its material C
• all of the above D

The thermistors are usually made of

• Metals with low temperature coefficient of resistivity A
• Metals with high temperature coefficient of resistivity B
• Metal oxides with high temperature coefficient of resistivity C
• Semi conducting materials having low temperature coefficient of resistivity D

The capacity of a parallel plat capacitor depends on the

• Type to metal used A
• Thickness of plates B
• Potential applied across the plates C
• Separation between the plates D

The conductivity of a superconductor is

• Infinite A
• Very large B
• Very small C
• Zero D

Potentiometer is more sensitive than voltmeter, because

• Voltmeter has a very high resistance A
• Voltmeter has a very low resistance B
• Potentiometer does not draw any current from a source of unknown potential difference C
• Potentiometer is sensitive D

Which one of the following is the unit of electric field intensity

• JC^-1 A
• Vm^-1 B
• Cm^-1 C
• CJ^-1 D

A (100 W , 200 W) bulb is connected to a 160 V power supply. The power consumption would be

• 64 W A
• 80 W B
• 100 W C
• 125 W D

If the length of the conductor is double and its cross sectional area is halved, its conductance will

• Increase four fold A
• Become one-fourth B
• Become one-half C
• Remains unchanged D

A uniform resistance wire of Length L and diameter d has a resistance R. Another wire of same material has length, 4L and diameter 2d, the resistance will be

• 2 R A
• R B
• R/2 C
• R/4 D

The potential difference across the conductors should be maintained constant by connecting the ends of wire to the terminal of a device called a source of

• power A
• current B
• resistance C
• temperature D

A 100 W, 200 V bulb is connected to a 160 volts supply. The actual power consumption would be

• 64 W A
• 80 W B
• 100 W C
• 125 W D

When a dielectric material is introduced between the plates of a charged condenser the electric field between the plates

• Decreases A
• Increases B
• No change C
• May increase or decresase D

The electric flux from a closed surface

• Is independent of the shape of the surface A
• Depends on the charge enclosed by the surface B
• Both a and b C
• None of the above D

Equal charges are given to two spheres of different radii. The potential will

• Be more on the smaller sphere A
• Be more on the bigger sphere B
• Be equal on both the sphere C
• Depend on the nature of the material of the sphere D

Resistance of a conductor is increased, the currant will

• Decrease A
• Increase B
• Remain the same C
• None of these D

Which one of the following has larger value of relative permitivity E_rat room temperature?

• Vaccum A
• Air B
• Glass C
• Water D

The liquid which conduct current is known as

• heating effect A
• chemical energy B
• electrolyte C
• ohm's law D

The relation V = IR represents

• Ampere law A
• Faraday's law B
• Ohm's law C
• Len's law D

The electric field will be uniform

• Near a positive point charge A
• Near a negative point charge B
• Between two oppositely charged parallel metal plates C
• None of above D

10⁶electrons are moving through a wire per second, the current developed is

• 1.6 x 10^-19 A
• 1 A B
• 1.6 x 10^-15 A C
• 10⁶A D

The energy stored in a charge capacitor

• 1/2CV² A
• 1/2C²V B
• 1/2C/V² C
• None of these D

Physicist George Simon ohm was a

• German physical A
• French physicist B
• Chinese physicist C
• Russian physicist D

• 5μF A
• 10μF B
• 3μF C
• 6μF D

The SI unit of electric field intensity is

• CN^-1 A
• NC^-1or Vm^-1 B
• JC^-1 C
• AV^-1 D

The material in the form of wire or rod or plate which leads the current into or cut of the electrolyte is known as

• voltmeters A
• resistance B
• electrode C
• current D

The potential difference across each resistance in series combination is

• same A
• different B
• zero C
• none of these D

Battery is charged in motor cars, which is based on

• Chemical effect A
• Magnetic effect B
• Electric effect C
• None D