ECAT Pre Engineering Physics Chapter 12 MCQ Test With Answer

If 2.2 kilowatt power is transmitted through a 10 ohm line at 22000 volt, the power loss in the form of heat will be

• 0.1 watt A
• 1 watt B
• 10 watt C
• 100 watt D

Coulomb's force between two point charges depends upon

• Magnitude of charges A
• Distance between them B
• Medium in which they are located C
• All of the above D

The excess (equal in number) of electrons that must be placed on each of two small spheres spaced 3 cm apart, with force of repulsion between the spheres to be 10^-19N, is

• 25 A
• 225 B
• 625 C
• 1250 D

Two point charges A and B separated by a distance R attract each other with a force of 12 x 10^-3N. The force between A and B when the charges on them are doubled and distance is halved

• 1.92 N A
• 19.2 N B
• 12 N C
• 0.192 N D

An alpha particle is accelerated through a potential difference of 10⁶volt. Its kinetic energy will be

• 1 MeV A
• 2 MeV B
• 4 MeV C
• 8 MeV D

A 60 W bulb operates on 220 V supply. The current flowing through the bulb is

• 11/3 A A
• 3 A B
• 3/11 A C
• 6 D

The charge carriers in electrolyte are positive and negative

• protons A
• electrons B
• ions C
• none of these D

One joule is equal to

• 1.6 x 10¹⁹eV A
• 6.25 x 10¹⁸eV B
• 1.6 x 18¹⁸eV C
• 6.25 x 10¹⁹eV D

The resistance of a conductor does not depend on its

• mass A
• resistivity B
• length C
• cross-sectional area D

In case of a parallel plate capacitor if the plate separation is doubled and plate area is halved, the capacitance becomes

• Four-fold A
• One-half B
• One-fourth C
• Zero D

The speed of randomly moving electrons depends upon

• pressure A
• volume B
• temperature C
• mass D

The charge per unit time through any cross-section of a conductor is called

• capacitance A
• electric power B
• current C
• potential difference D

The unit of intensity of electric field is

• newton/coluomb A
• jule/coluomb B
• volt x metre C
• newton/metre D

The unit of conductance is

• ohm A
• meter B
• mho C
• ohm-meter 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

• 5μF A
• 10μF B
• 3μF C
• 6μF 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

A metal plate of thickness half the separation between the capacitor plates of capacitance C is inserted. The new capacitance is

• C A
• C/2 B
• Zero C
• 2C D

Physicist George Simon ohm was a

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

The relation V = IR represents

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

One electron volt is equal to

• 1.6 x 1019eV A
• 6.25 x 1018 eV B
• 1.6 x 1018 eV C
• 6.25 x 1019eV D

The SI unit of capacitance is

• Farad A
• Henry B
• Ohm C
• Volt D

The resistance of 20 cm long wire is 10Ω. When the length is changed to 40 cm. The new resistance is

• 10Ω A
• 20Ω B
• 30Ω C
• 40Ω D

The statement "the electric force of repulsion or attraction between two point charges is directly proportional to the product of the charges and inversely proportional to square of the distance between them" refer to

• Coulomb's law A
• Gauss's law B
• Biot-Sarwat law C
• Ampere's law D

What is the current is a 2 x 10⁶ohm resistor having a potential difference of 2 x 10³volts?

• 10^-1A A
• 10^-2A B
• 10^-4A C
• 1 mA D

The electric intensity outside the two oppositely charged parallel metal plates is

• Maximum A
• Minimum B
• Zero C
• Infinite D

The value of electrical constant of proportionality k is

• 9 x 10⁹Nm²C^-2 A
• 9 x 10^-9Nm²C^-2 B
• 9 x 10¹⁰Nm²C² C
• 9.85 x 10^-12N^-1C^-2 D

Ohm is the unit of

• current A
• capacitance B
• energy C
• resistance D

The liquid which conduct current is known as

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

The charge carriers in gases are

• electrons A
• ions B
• protons C
• ions and electrons D