A plane electromagnetic wave of frequency 20 MHz travels through a space along x-direction. If the electric field vector at a certain point in space is 6 Vm⁻¹, then what is the magnetic field vector […]
If the velocity of charged particle has both perpendicular and parallel components while moving through a magnetic field, then what is the path followed by a charged particle?
Options
(a) Circular (b) Elliptical […]
A solenoid has length 0.4 cm, radius 1 cm and 400 turns of wire. If a current of 5 A is passed through this solenoid, then what is the magnetic field inside the solenoid?
A susceptibility of a certain magnetic material is 400. What is the class of the magnetic material?
Options
(a) Diamagnetic (b) Paramagnetic (c) Ferromagnetic (d) Ferroelectric
Correct Answer:
Ferromagnetic
Explanation:
No explanation available. […]
Diameter of the objective of a telescope is 200 cm. What is the resolving power of a telescope? Take wavelength of light=5000Å.
Options
(a) 6.56×10⁶ (b) 3.28×10⁵ (c) 1×10⁶ (d) 3.28×10⁶
Correct Answer:
3.28×10⁶
A focal length of a lens is 10 cm. What is power of a lens in dioptre?
Options
(a) 0.1 D (b) 10 D (c) 15 D (d) 1 D
Correct Answer:
10 […]
An object placed at 20 cm in front of a concave mirror produces three times magnified real image. What is the focal length of the concave mirror?
Options
(a) 15 cm (b) 6.6 cm […]
A polarised light of intensity I₀ is passed through another polariser whose pass axis makes an angle of 60⁰ with the pass axis of the former. What is the intensity of emergent polarised light from […]
Wavefront is the locus of all points, where the particles of the medium vibrate with the same
Options
(a) phase (b) amplitude (c) frequency (d) period
Correct Answer:
phase
Explanation:
On the wave front, […]
Two capacitors of 10pF and 20pF are connected to 200V and 100V sources, respectively. If they are connected by the wire, then what is the common potential of the capacitors?
Options
(a) 133.3V […]
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