Users Also Read
Read MCQ's/Objective questions
MCQ's Search Engine
Analog Electronics
Automatic Control Systems
Communication Systems
Digital Electronics
Electronic Devices and Circuits
Materials and Components
Measurements and Instrumentation
Microprocessors
Microwave Communication
Networks Analysis and Synthesis
Power Electronics
Radio Receivers
Satellite Communication
Signals and Systems
Exam Questions Papers
Matching Questions
Home⇒ Engineering⇒
Electromagnetic field theory
1-Dont try to cram or spend more time here just read it fast and cover syllabus then practice MCQ's cheptor of same topic to check your progress. . |
2-Wrong options are also given but dont concentrate there, Right answer is in bold format. |
Q1 ⇒ In cellphone communication base antennas are connected to other base antennas in line of sight communication [other wrong options] [Discuss in forum] ionospheric propagation ground wave propagation medium wave propagation |
Q2 ⇒ Half power point directions for broadside is 60° [other wrong options] [Discuss in forum] 30° 45° at any angle |
Q3 ⇒ Microwave signals transmitted towards the sky are transmitted through the ionosphere [other wrong options] [Discuss in forum] strongly absorbed by the ionosphere strongly reflected by the ionosphere unable to reach the ionosphere because of strong absorption in the lower atmosphere |
Q4 ⇒ Which antenna is frequently used for local area transmission at UHF/VHF? Ground monopole [other wrong options] [Discuss in forum] Turnstile antenna Slot antenna Loop antenna |
Q5 ⇒ A wavelength of 1 mm could be expected in EHF [other wrong options] [Discuss in forum] VLF HF SHF |
Q6 ⇒ Which of the following frequencies cannot be used for reliable beyond-the-horizon terrestrial communications without repeaters? 12 GHz [other wrong options] [Discuss in forum] 25 kHz 15 MHz 750 MHz |
Q7 ⇒ Cassergain feed is used with a parabolic reflector to allow the feed to be placed at a convenient point [other wrong options] [Discuss in forum] increase the gain of the system increase the beamwidth of the system reduce the size of the main reflector |
Q8 ⇒ The directivity of 20 turn helix having a = 12° circumference equal to one wavelength, will be 18 dB [other wrong options] [Discuss in forum] 1.8 dB 6 dB 12 dB |
Q9 ⇒ A dipole antenna was radiating with some excitation in free space radiating a certain amount of the power. If this antenna is immersed in a lake where water is non-dissipative but has a dielectric constant of 81, the radiated power with the same excitation will remain the same [other wrong options] [Discuss in forum] decrease to finite non-zero value increase decrease to zero |
Q10 ⇒ A broadside array is shown in figure in which the elements are placed at equal distances. The direction of maximum radiation is represented AA [other wrong options] [Discuss in forum] BB CC DD |
Q11 ⇒ Antenna commonly used for microwave links are paraboloidal dishes [other wrong options] [Discuss in forum] loop antennas log periodic antennas rhombic antennas |
Q12 ⇒ Frequencies in the UHF range propagate by means of space wave [other wrong options] [Discuss in forum] surface waves sky waves ground waves |
Q13 ⇒ According to maximum power transfer theorem, if the load is inductive, the source should be capacitive [other wrong options] [Discuss in forum] inductive resistive any of the above |
Q14 ⇒ Unit of e is __________ . Farad/metre [other wrong options] [Discuss in forum] coulomb/newton-metre coulomb2/newton-metre Farad2/metre |
Q15 ⇒ Magnesium is alloyed with conducting materials for antenna primarily with the purpose of reducing weight [other wrong options] [Discuss in forum] increasing efficiency improving radiative power increasing density |
Q16 ⇒ The attenuation factor in parallel plane guides is given by a = power lost per unit length/2 x power transmitted [other wrong options] [Discuss in forum] a = power lost/power transmitted a = 2 x power lost/power transmitted a is always constant |
Q17 ⇒ The frequencies in ultra high frequency range are propagated by means of __________ waves space [other wrong options] [Discuss in forum] surface ground sky |
Q18 ⇒ Surface waves can propagate on Piezoelectric substrates. TRUE [other wrong options] [Discuss in forum] FALSE |
Q19 ⇒ Which one is correct option? Both (a) and (b) [other wrong options] [Discuss in forum] TEM mode exist in free space of infinite boundary TEM mode exist in two conductor pattern system for finite-boundary TEM mode exist in waveguide only |
Q20 ⇒ Mutual impedance is not depend upon self impedance [other wrong options] [Discuss in forum] magnitude of induced current tuning condition phase relationship between induced and original currents |
Or |