- AParallel to each other
- BAntiparallel to each other
- CPerpendicular to each other
- DNone of these.
Explanation:
Force on a current carrying wire placed in a magnetic field is given by F = I (l × B) So when the wires are perpendicular the magnetic field produced by one of them will be along the length of the other and we know cross product of two vectors along the same direction is zero.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Select the correct statement
|
(a) In a full wave rectifier, two diodes work alternately |
|
(b) In a full wave rectifier, two diodes work simultaneously |
|
(c) The efficiency of full wave and half wave rectifiers is same |
|
(d) The full wave rectifier is bi-directional. |
Wires P and Q have the same resistance at ordinary (room) temperature. When heated, resistance of P increases and that of Q decreases. We conclude that
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(a) P and Q are conductors of different materials |
|
(b) P is N-type semiconductor and Q is P-type semiconductor |
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(c) P is semiconductor and Q is conductor |
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(d) P is conductor and Q is semiconductor |
If 2.2 kilowatt power is transmitted through a 10 ohm line at 22000 volt, the power loss in the form of heat will be
|
(a) 0.1 watt |
(b) 1 watt |
(c) 10 watt |
(d) 100 watt |
An ionization chamber with parallel conducting plates as anode and cathode has 5 electrons and the same number of singly-charged positive ions per
. The electrons are moving at 0.4 m/s. The current density from anode to cathode is
. The velocity of positive ions moving towards cathode is
|
(a) 0.4 m/s |
(b) 16 m/s |
(c) Zero |
(d) 0.1 m/s |
A particle with charge q, moving with a momentum p, enters a uniform magnetic field normally. The magnetic field has magnitude B and is confined to a region of width d, where d <
, The particle is deflected by an angle θ in crossing the field

|
(a) sinθ = |
(b) sinθ = |
(c) sinθ = |
(d) sinθ = |
The wavelength of emission line spectrum and absorption line spectrum of a substance are related as
|
(a) Absorption has larger value |
(b) Absorption has smaller value |
|
(c) They are equal |
(d) No relation |
The momentum of a photon in an X-ray beam of
metre wavelength is
|
(a) 1.5 |
(b) 6.6 |
|
(c) 6.6 |
(d) 2.5 |