Description : Find the force that exists in an electromagnetic wave. a) Electrostatic force b) Magnetostatic force c) Lorentz force d) Electromotive force
Last Answer : c) Lorentz force
Description : For time varying currents, the field or waves will be a) Electrostatic b) Magneto static c) Electromagnetic d) Electrical
Last Answer : c) Electromagnetic
Description : Find the Lorentz force due to a conductor of length 2m carrying a current of 1.5A and magnetic flux density of 12 units. a) 24 b) 36 c) 32 d) 45
Last Answer : c) 32
Description : Find the Lorentz force of a charge 2.5C having an electric field of 5 units and magnetic field of 7.25 units with a velocity 1.5m/s. a) 39.68 b) 68.39 c) 86.93 d) 93.68
Last Answer : a) 39.68
Description : Lorentz force is based on, a) Dot product b) Cross product c) Both dot and cross product d) Independent of both
Last Answer : b) Cross product
Description : What is magneto motive force?
Last Answer : The force, which drives the magnetic flux through a magnetic circuit, is called the magneto motive force.
Description : Define the following terms: i) Magnetic flux density, ii) Reluctance, iii) Magneto-motive force, iv) Permeance.
Last Answer : (i) Magnetic flux density (B): It is the magnetic flux per unit area measured at right angles to the flux path. (Its unit is weber/m2 or tesla). (ii) Reluctance: It is the ... flux to set up through it and it is reciprocal of reluctance. Permeance = 1/ Reluctance. Unit: weber/ampere.
Last Answer : The magneto-motive force is the sum of all currents embraced by one line of magnetic field.
Description : A current carrying conductor is associated with – (1) a magnetic field (2) an electric field (3) an electro-magnetic field (4) an electrostatic field
Last Answer : (3) an electro-magnetic field Explanation: A current carrying conductor, such as a metal wire, will produce a magnetic field around it because of the motion of charge within the wire itself. This motion produces or sets up a magnetic field around the wire in the form of concentric circles.
Description : A current carrying conductor is associated with (1) a magnetic field (2) an electric field (3) an electro-magnetic field (4) an electrostatic field
Last Answer : an electro-magnetic field
Description : What are the types of induced electro motive force?
Last Answer : a. Dynamically induced emf. b. Statically induced emf. Statically induced emf can be further divided into two groups. a. Mutually induced emf. b. Self induced emf.
Description : What is electro-motive force (emf) or voltage?
Last Answer : It is the pressure that moves the electrons to flow in any conductor. It is also known as electromotive force voltage. Its symbol is ‘E’ or ‘V’ and measuring unit is volt measured by voltmeter.
Description : The power in a electromagnetic wave with electric field and magnetic field intensities 12 and 8 respectively is a) 96 b) 12 c) 8 d) 48
Last Answer : d) 48
Description : The electric and magnetic field components in the electromagnetic wave propagation are in phase. State True/False. a) True b) False
Last Answer : a) True
Description : An example for electromagnetic wave propagation is a) refrigerator b) electric fan c) mobile transponder d) relays in actuators
Last Answer : c) mobile transponder
Description : The vectors of the electromagnetic wave propagation can be expressed in a) Dot product b) Cross product c) Unit vector d) Perpendicular vector
Description : Which components exist in an electromagnetic wave? a) Only E b) Only H c) Both E and H d) Neither E or H
Last Answer : c) Both E and H
Description : In electromagnetic waves, the electric field will be perpendicular to which of the following? a) Magnetic field intensity b) Wave propagation c) Both H and wave direction d) It propagates independently
Last Answer : c) Both H and wave direction
Description : Justify electromagnetic wave is said to be transverse wave.
Last Answer : Transverse electromagnetic wave:- The electromagnetic waves are oscillations which propagate through free space. In electromagnetic waves the direction of electric field, magnetic field & propagation are ... electric field vector with respect to the surface (i.e. looking at the horizon)
Description : Calculate the skin depth of a conductor, having a conductivity of 200 units. The wave frequency is 10 GHz in air. a) 355.8 b) 3.558 c) 35.58 d) 0.3558
Last Answer : a) 355.8
Description : The skin depth of a wave with phase constant of 12 units inside a conductor is a) 12 b) 1/12 c) 24 d) 1/24
Last Answer : b) 1/12
Description : The propagation constant of the wave in a conductor with air as medium is a) √(ωμσ) b) ωμσ c) √(ω/μσ) d) ω/μσ
Last Answer : a) √(ωμσ)
Description : The expression for velocity of a wave in the conductor is a) V = √(2ω/μσ) b) V = √(2ωμσ) c) V = (2ω/μσ) d) V = (2ωμσ)
Last Answer : a) V = √(2ω/μσ)
Description : Calculate the velocity of wave propagation in a conductor with frequency 5 x 10 8 rad/s and phase constant of 3 x 10 8 units. a) 3/5 b) 15 c) 5/3 d) 8
Last Answer : c) 5/3
Description : Not an example for actuator (a) Optical fiber (b) Shape memory alloys (c) Magneto-strictive materials (d) Electro-/Magneto-rheological fluids
Last Answer : (a) Optical fiber
Description : Corona discharge is related to the operation of a/an (A) Induction motor (B) Electrostatic precipitator (C) Fast breeder reactor (D) Magneto hydrodynamic generator (MHD)
Last Answer : Option B
Description : According to Faraday’s law, EMF stands for a) Electromagnetic field b) Electromagnetic force c) Electromagnetic friction d) Electromotive force
Last Answer : d) Electromotive force
Description : The charge density of a electrostatic field is given by a) Curl of E b) Divergence of E c) Curl of D d) Divergence of D
Last Answer : d) Divergence of D
Description : The permittivity is also called a) Electrostatic energy b) Dielectric constant c) Dipole moment d) Susceptibility
Last Answer : b) Dielectric constant
Description : If the electric potential is given, which of the following cannot be calculated? a) Electrostatic energy b) Electric field intensity c) Electric flux density d) Permittivity
Last Answer : a) Electrostatic energy
Description : The electrostatic energy in an electric field does not depend on which of the following? a) Magnitude of charges b) Permittivity c) Applied electric field d) Flux lines
Last Answer : c) Applied electric field
Description : Find the maximum force of the conductor having length 60cm, current 2.75A and flux density of 9 units. a) 14.85 b) 18.54 c) 84.25 d) 7.256
Last Answer : a) 14.85
Description : The force on a conductor of length 12cm having current 8A and flux density 3.75 units at an angle of 300 is a) 1.6 b) 2 c) 1.4 d) 1.8
Last Answer : d) 1.8
Description : Find the force on a conductor of length 12m and magnetic flux density 20 units when a current of 0.5A is flowing through it. a) 60 b) 120 c) 180 d) 200
Last Answer : b) 120
Description : The expression F⃗ = qE⃗⃗ + q(v⃗ × B⃗⃗) represents _________ force a) Maxwell b) Gravitational c) Magnetic d) Lorentz
Last Answer : d) Lorentz
Description : The propagation of the electromagnetic waves can be illustrated by a) Faraday law b) Ampere law c) Flemming rule d) Coulomb law
Last Answer : c) Flemming rule
Description : Harmonic electromagnetic fields refer to fields varying sinusoidally with respect to time. State True/False. a) True b) False
Description : Which quantity is solenoidal in the electromagnetic theory? a) Electric field intensity b) Electric flux density c) Magnetic field intensit d) Magnetic flux density
Last Answer : d) Magnetic flux density
Description : Identify the devices that do not use electromagnetic energy. a) Television b) Washing machine c) Microwave oven d) Mobile phones
Last Answer : b) Washing machine
Description : Electromagnetic waves are longitudinal in nature. State True/False. a) True b) False
Last Answer : b) False
Description : The capacitance of a material refers to a) Ability of the material to store magnetic field b) Ability of the material to store electromagnetic field c) Ability of the material to store electric field d) Potential between two charged plates
Last Answer : c) Ability of the material to store electric field
Description : Which of the following are not vector functions in Electromagnetic? a) Gradient b) Divergence c) Curl d) There is no non- vector functions in Electromagnetics
Last Answer : d) There is no non- vector functions in Electromagnetics
Description : State advantages & disadvantages of electromagnetic flow meter.
Last Answer : Advantage: Provides wide linear range. 2) Ability to measure reverses flow. 3) Gives rapid response to flow changes. 4) No obstruction is created to flow. 5) It can handle corrosive as ... and pipe networks with relatively short inside diameters. 3) It is useful for electrically conducting fluid.
Description : i) Explain electromagnetic spectrum with neat diagram. ii) Explain atmospheric noise with example.
Last Answer : Explanation:- The electromagnetic spectrum is the range of frequencies of electromagnetic radiation and their respective wavelengths The electromagnetic spectrum covers ... spread over the complete frequency spectrum used for radio communication. Example: Lightning
Description : What is the frequency range of VHF electromagnetic waves? A) 30-300 kHz B) 30-3000 kHz C) 30-300 MHz D) 30-3000 MHz
Last Answer : What is the frequency range of VHF electromagnetic waves? A) 30-300 kHz B) 30-3000 kHz C) 30-300 MHz D) 30-3000 MHz
Description : The electric and magnetic fields vary with time in which of the following fields? a) DC b) AC c) Static d) It does not vary with time
Last Answer : b) AC
Description : The line integral of which parameter is zero for static fields? a) E b) H c) D d) B
Last Answer : a) E
Description : For static fields, the curl of E will be a) Rotational b) Irrotational c) Solenoidal d) Divergent
Last Answer : b) Irrotational
Description : Which of the following identities is always zero for static fields? a) Grad(Curl V) b) Curl(Div V) c) Div(Grad V) d) Curl(Grad V)
Last Answer : d) Curl(Grad V)