Physics MCQs

What is the fundamental equation of electromagnetism?
a) Newton’s second law
b) SchrÃ¶dinger’s equation
c) Maxwell’s equations
d) Einstein’s field equations

What is the SI unit of electric charge?
a) Coulomb
b) Ampere
c) Volt
d) Ohm

What is the direction of the electric field at a point due to a positive point charge?
c) Tangential
d) Parallel to the charge

According to Gauss’s law, the electric flux through a closed surface is proportional to:
a) The total charge enclosed by the surface
b) The area of the surface
c) The electric field inside the surface
d) The potential difference across the surface
Answer: a) The total charge enclosed by the surface

What is the direction of the magnetic field inside a solenoid?
a) Along the axis of the solenoid
d) Tangential to the solenoid
Answer: a) Along the axis of the solenoid

What is the relationship between electric field and electric potential?
a) Electric potential is the negative gradient of the electric field
b) Electric potential is the integral of the electric field
c) Electric potential is the curl of the electric field
d) Electric potential is proportional to the electric field
Answer: a) Electric potential is the negative gradient of the electric field

What is the SI unit of magnetic field strength?
a) Tesla
b) Weber
c) Henry

What is the direction of the magnetic field inside a current-carrying wire?
a) Along the wire in the direction of current flow
b) Opposite to the direction of current flow
Answer: a) Along the wire in the direction of current flow

According to Faraday’s law of electromagnetic induction, the induced electromotive force in a loop is proportional to:
a) The rate of change of magnetic field through the loop
b) The resistance of the loop
c) The current flowing through the loop
d) The area of the loop
Answer: a) The rate of change of magnetic field through the loop

What is the relationship between magnetic field and magnetic flux?
a) Magnetic field is the negative gradient of magnetic flux
b) Magnetic field is the integral of magnetic flux
c) Magnetic field is proportional to magnetic flux
d) Magnetic field is inversely proportional to magnetic flux

Which law describes the force between two electric charges?
a) Ampere’s law
b) Ohm’s law
c) Coulomb’s law
d) Gauss’s law

What is the direction of the magnetic field around a straight current-carrying wire?
a) Circular, parallel to the wire
b) Circular, perpendicular to the wire
c) Linear, along the wire
d) Linear, perpendicular to the wire
Answer: b) Circular, perpendicular to the wire

What is the relationship between current and resistance in an electrical circuit?
a) Current is directly proportional to resistance
b) Current is inversely proportional to resistance
c) Current is independent of resistance
d) Current is inversely proportional to the square of resistance
Answer: b) Current is inversely proportional to resistance

What is the principle behind an electric generator?
a) Conversion of mechanical energy into electrical energy
b) Conversion of electrical energy into mechanical energy
c) Conversion of heat energy into electrical energy
d) Conversion of magnetic energy into electrical energy
Answer: a) Conversion of mechanical energy into electrical energy

What is the relationship between electric current and electric potential difference (voltage) in a circuit?
a) Electric current is directly proportional to electric potential difference
b) Electric current is inversely proportional to electric potential difference
c) Electric current is independent of electric potential difference
d) Electric current is directly proportional to the square of electric potential difference
Answer: a) Electric current is directly proportional to electric potential difference

According to Lenz’s law, the direction of an induced current in a loop is such that it:
a) Opposes the change in magnetic field that caused it
b) Supports the change in magnetic field that caused it
c) Creates a magnetic field in the same direction as the inducing field
d) Creates a magnetic field in the opposite direction of the inducing field
Answer: a) Opposes the change in magnetic field that caused it

What is the principle behind an electric motor?
a) Conversion of mechanical energy into electrical energy
b) Conversion of electrical energy into mechanical energy
c) Conversion of heat energy into electrical energy
d) Conversion of magnetic energy into electrical energy
Answer: b) Conversion of electrical energy into mechanical energy

What is the relationship between the strength of an electromagnet and the number of turns in the coil?
a) Strength is directly proportional to the number of turns
b) Strength is inversely proportional to the number of turns
c) Strength is independent of the number of turns
d) Strength is directly proportional to the square of the number of turns
Answer: a) Strength is directly proportional to the number of turns

What is the relationship between the speed of light and the permeability and permittivity of free space?
a) Speed of light is directly proportional to the square root of permeability and permittivity
b) Speed of light is inversely proportional to the square root of permeability and permittivity
c) Speed of light is independent of permeability and permittivity
d) Speed of light is directly proportional to the product of permeability and permittivity
Answer: b) Speed of light is inversely proportional to the square root of permeability and permittivity

What is the relationship between the direction of an electric field and the direction of the force experienced by a positive test charge?
a) The force and electric field have the same direction
b) The force and electric field have opposite directions
c) The force is perpendicular to the electric field
d) The force is independent of the electric field
Answer: a) The force and electric field have the same direction

What is the principle behind a transformer?
a) Conversion of mechanical energy into electrical energy
b) Conversion of electrical energy into mechanical energy
c) Conversion of heat energy into electrical energy
d) Induction of a changing voltage in a coil by a changing magnetic field
Answer: d) Induction of a changing voltage in a coil by a changing magnetic field

What is the relationship between the power consumed by an electrical device and the current flowing through it?
a) Power is directly proportional to the current
b) Power is inversely proportional to the current
c) Power is independent of the current
d) Power is directly proportional to the square of the current
Answer: a) Power is directly proportional to the current

According to the right-hand rule, the direction of the magnetic field around a current-carrying wire is determined by:
a) The direction of current flow in the wire
b) The direction of electric field inside the wire
c) The direction of electric potential difference across the wire
d) The direction of gravitational force acting on the wire
Answer: a) The direction of current flow in the wire

What is the relationship between the magnetic field and the magnetic force experienced by a charged particle moving in a magnetic field?
a) The magnetic force is perpendicular to both the magnetic field and the velocity of the particle
b) The magnetic force is parallel to the magnetic field and perpendicular to the velocity of the particle
c) The magnetic force is parallel to both the magnetic field and the velocity of the particle
d) The magnetic force is independent of the magnetic field and the velocity of the particle
Answer: a) The magnetic force is perpendicular to both the magnetic field and the velocity of the particle

What is the principle behind a cathode ray tube (CRT)?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Conversion of electrical energy into light energy
Answer: d) Conversion of electrical energy into light energy

What is the relationship between the magnetic field and the magnetic flux density?
a) Magnetic field and magnetic flux density are the same quantity
b) Magnetic field is the integral of magnetic flux density
c) Magnetic field is proportional to magnetic flux density
d) Magnetic field is inversely proportional to magnetic flux density
Answer: a) Magnetic field and magnetic flux density are the same quantity

What is the relationship between the electric field and the electric potential energy of a charged particle?
a) Electric field is the derivative of electric potential energy
b) Electric field is the negative gradient of electric potential energy
c) Electric field is the integral of electric potential energy
d) Electric field is proportional to electric potential energy
Answer: b) Electric field is the negative gradient of electric potential energy

What is the principle behind a capacitor?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Storage of electric potential energy in an electric field
d) Induction of a changing voltage in a coil by a changing magnetic field
Answer: c) Storage of electric potential energy in an electric field

What is the relationship between the radius of curvature of an electric field line and the strength of the electric field?
a) Smaller radius of curvature indicates stronger electric field
b) Larger radius of curvature indicates stronger electric field
c) Radius of curvature is independent of the strength of the electric field
d) Radius of curvature is inversely proportional to the strength of the electric field

According to Lenz’s law, the direction of an induced magnetic field in a closed loop is such that it:
a) Opposes the change in magnetic flux that caused it
b) Supports the change in magnetic flux that caused it
c) Creates a magnetic field in the same direction as the inducing field
d) Creates a magnetic field in the opposite direction of the inducing field
Answer: a) Opposes the change in magnetic flux that caused it

What is the relationship between the speed of light and the frequency and wavelength of an electromagnetic wave?
a) Speed of light is directly proportional to the frequency and inversely proportional to the wavelength
b) Speed of light is directly proportional to the wavelength and inversely proportional to the frequency
c) Speed of light is directly proportional to the product of frequency and wavelength
d) Speed of light is independent of the frequency and wavelength
Answer: b) Speed of light is directly proportional to the wavelength and inversely proportional to the frequency

What is the principle behind an antenna?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Conversion of electrical energy into electromagnetic radiation

What is the relationship between the intensity of electromagnetic radiation and the square of the amplitude of the electric field?
a) Intensity is directly proportional to the square of the amplitude of the electric field
b) Intensity is inversely proportional to the square of the amplitude of the electric field
c) Intensity is independent of the amplitude of the electric field
d) Intensity is directly proportional to the amplitude of the electric field
Answer: a) Intensity is directly proportional to the square of the amplitude of the electric field

What is the principle behind a microwave oven?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Conversion of electrical energy into microwave radiation

What is the relationship between the direction of propagation of an electromagnetic wave and the orientation of the electric and magnetic fields?
a) Electric and magnetic fields are perpendicular to each other and perpendicular to the direction of propagation
b) Electric and magnetic fields are parallel to each other and parallel to the direction of propagation
c) Electric and magnetic fields are perpendicular to each other and parallel to the direction of propagation
d) Electric and magnetic fields are parallel to each other and perpendicular to the direction of propagation
Answer: a) Electric and magnetic fields are perpendicular to each other and perpendicular to the direction of propagation

What is the principle behind a laser?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Amplification of light by stimulated emission of radiation

What is the relationship between the electric field and the magnetic field in an electromagnetic wave?
a) Electric and magnetic fields are parallel to each other
b) Electric and magnetic fields are perpendicular to each other
c) Electric and magnetic fields are independent of each other
d) Electric and magnetic fields are inversely proportional to each other
Answer: b) Electric and magnetic fields are perpendicular to each other

According to Gauss’s law for magnetism, the magnetic flux through a closed surface is proportional to:
a) The total magnetic charge enclosed by the surface
b) The area of the surface
c) The magnetic field inside the surface
d) The potential difference across the surface
Answer: a) The total magnetic charge enclosed by the surface

What is the relationship between the wavelength and frequency of an electromagnetic wave?
a) Wavelength is directly proportional to frequency
b) Wavelength is inversely proportional to frequency
c) Wavelength is independent of frequency
d) Wavelength is inversely proportional to the square of the frequency
Answer: b) Wavelength is inversely proportional to frequency

What is the principle behind a photovoltaic cell?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Conversion of light energy into electrical energy
Answer: d) Conversion of light energy into electrical energy

What is the relationship between the resistance and the length and cross-sectional area of a wire?
a) Resistance is directly proportional to the length and inversely proportional to the cross-sectional area of the wire
b) Resistance is inversely proportional to the length and directly proportional to the cross-sectional area of the wire
c) Resistance is directly proportional to both the length and the cross-sectional area of the wire
d) Resistance is inversely proportional to both the length and the cross-sectional area of the wire
Answer: a) Resistance is directly proportional to the length and inversely proportional to the cross-sectional area of the wire

What is the principle behind an electric circuit breaker?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Disruption of current flow in the circuit to protect against overloads or short circuits
Answer: d) Disruption of current flow in the circuit to protect against overloads or short circuits

What is the relationship between the resistivity of a material and its electrical conductivity?
a) Resistivity is inversely proportional to electrical conductivity
b) Resistivity is directly proportional to electrical conductivity
c) Resistivity and electrical conductivity are independent of each other
d) Resistivity is directly proportional to the square of electrical conductivity
Answer: a) Resistivity is inversely proportional to electrical conductivity

What is the principle behind a superconductor?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Zero resistance to electrical current flow at low temperatures
Answer: d) Zero resistance to electrical current flow at low temperatures

What is the relationship between the current flowing through a resistor and the voltage across it?
a) Current is directly proportional to voltage
b) Current is inversely proportional to voltage
c) Current is independent of voltage
d) Current is directly proportional to the square of voltage
Answer: a) Current is directly proportional to voltage

What is the principle behind a magnetic resonance imaging (MRI) machine?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Utilization of magnetic fields and radio waves to generate detailed images of internal body structures
Answer: d) Utilization of magnetic fields and radio waves to generate detailed images of internal body structures

What is the relationship between the electric potential and the electric field at a point in an electric field?
a) Electric potential is the negative gradient of the electric field
b) Electric potential is the integral of the electric field
c) Electric potential is the curl of the electric field
d) Electric potential is proportional to the electric field
Answer: a) Electric potential is the negative gradient of the electric field

What is the principle behind an electric bell?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Conversion of electrical energy into sound energy
Answer: a) Conversion of electrical energy into mechanical energy

What is the relationship between the magnetic field strength and the magnetic permeability of a material?
a) Magnetic field strength is inversely proportional to magnetic permeability
b) Magnetic field strength is directly proportional to magnetic permeability
c) Magnetic field strength and magnetic permeability are independent of each other
d) Magnetic field strength is inversely proportional to the square of magnetic permeability
Answer: b) Magnetic field strength is directly proportional to magnetic permeability

What is the principle behind an electrically conductive wire?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Ease of flow of electric charges through the wire due to the presence of free electrons
Answer: d) Ease of flow of electric charges through the wire due to the presence of free electrons

What is the relationship between the current and the rate of flow of electric charges?
a) Current is directly proportional to the rate of flow of electric charges
b) Current is inversely proportional to the rate of flow of electric charges
c) Current is independent of the rate of flow of electric charges
d) Current is directly proportional to the square of the rate of flow of electric charges
Answer: a) Current is directly proportional to the rate of flow of electric charges

What is the principle behind a Van de Graaff generator?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Accumulation of electric charge on a hollow metal sphere by means of a moving belt
Answer: d) Accumulation of electric charge on a hollow metal sphere by means of a moving belt

What is the relationship between the voltage and the electric potential energy of a charged particle?
a) Voltage is the negative gradient of electric potential energy
b) Voltage is the integral of electric potential energy
c) Voltage is proportional to electric potential energy
d) Voltage is independent of electric potential energy
Answer: c) Voltage is proportional to electric potential energy

What is the principle behind a step-up transformer?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Increase in voltage by increasing the number of turns in the secondary coil
Answer: d) Increase in voltage by increasing the number of turns in the secondary coil

What is the relationship between the capacitance of a capacitor and the area of the plates?
a) Capacitance is directly proportional to the area of the plates
b) Capacitance is inversely proportional to the area of the plates
c) Capacitance is independent of the area of the plates
d) Capacitance is directly proportional to the square of the area of the plates
Answer: a) Capacitance is directly proportional to the area of the plates

What is the principle behind a magnetic levitation (maglev) train?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Utilization of magnetic fields to suspend and propel the train without contact with the track
Answer: d) Utilization of magnetic fields to suspend and propel the train without contact with the track

What is the relationship between the electric field and the electric force experienced by a charged particle?
a) The electric force is parallel to the electric field
b) The electric force is perpendicular to the electric field
c) The electric force is independent of the electric field
d) The electric force is inversely proportional to the electric field
Answer: a) The electric force is parallel to the electric field

According to Faraday’s law of electromagnetic induction, the magnitude of the induced electromotive force is proportional to:
a) The resistance of the loop
b) The current flowing through the loop
c) The rate of change of magnetic field through the loop
d) The area of the loop
Answer: c) The rate of change of magnetic field through the loop

What is the relationship between the electric field and the electric flux through a closed surface?
a) Electric field is directly proportional to the electric flux
b) Electric field is inversely proportional to the electric flux
c) Electric field and electric flux are independent of each other
d) Electric field is inversely proportional to the square of the electric flux
Answer: a) Electric field is directly proportional to the electric flux

What is the principle behind an electric guitar?
a) Conversion of electrical energy into mechanical energy
b) Conversion of heat energy into electrical energy
c) Conversion of magnetic energy into electrical energy
d) Conversion of mechanical vibrations into electrical signals for amplification
Answer: d) Conversion of mechanical vibrations into electrical signals for amplification