If a magnetic substance is brought near the north or the south pole of a bar magnet, it is:
Options
(a) repelled by the north pole and attracted by the south pole (b) […]
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. […]
A proton beam enters a magnetic field of 10⁻⁴ Wb/m² normally. If the specific charge of the proton is 10¹¹ C/kg and its velocity is 10⁹ m/s, then the radius of the circle described will […]
A freely suspended bar magnet aligns itself in
Options
(a) A direction (b) A particular direction (c) Any direction (d) Depends on mass of target
Correct Answer:
A particular direction
Explanation:
A freely suspended […]
There is a ring of radius r having linear charge density λ and rotating with a uniform angular velocity ω. The magnetic field produced by this ring at its own centre would be
Options […]
Magnetism of a magnet is due to
Options
(a) Cosmic rays (b) Large magnet at the centre of Earth (c) Spins of electrons (d) Gravitation
Correct Answer:
Spins of electrons
Explanation:
No explanation […]
The radius of curvature of a concave mirror is 24 cm and the imager is magnified by 1.5 times. The object distance is
Options
(a) 20 cm (b) 8 cm (c) 16 cm […]
The focal length of the objective of a terrestrial telescope is 80 cm and it is adjusted for parallel rays, then its power is 20. If the focal length of erecting lens is 20 cm, […]
An object is placed at a distance of 10 cm from a co-axial combination of two lenses A and B in contact. The combination forms a real image three times the size of the object. […]
A short linear object of length L lies on the axis of a spherical mirror of focal length f at a distance u form the mirror. Its image has an axial length L’ equal to […]
2017 Copyright Doctor Dreams Training Academy