A horizontal straight conductor kept in north-south direction falls under gravity, then
|
(a) A current will be induced from South to North |
|
(b) A current will be induced from North to South |
|
(c) No induce e.m.f. along the length of conductor |
|
(d) An induced e.m.f. is generated along the length of conductor |
(c) No induce e.m.f. along the length of conductor
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Light wave is travelling along y-direction. If the corresponding 
vector at any time is along the x-axis, the direction of 
vector at that time is along
|
(a) y-axis |
(b) x-axis |
(c) + z-axis |
(d) – z axis |
4 eV is the energy of the incident photon and the work function in 2eV. What is the stopping potential
|
(a) 2V |
(b) 4V |
(c) 6V |
(d) 2 |
A cylindrical bar magnet is kept along the axis of a circular coil. If the magnet is rotated about its axis, then
|
(a) A current will be induced in a coil |
|
(b) No current will be induced in a coil |
|
(c) Only an e.m.f. will be induced in the coil |
|
(d) An e.m.f. and a current both will be induced in the coil |
A step-up transformer operates on a 230 V line and supplies a load of 2 ampere. The ratio of the primary and secondary windings is 1 : 25. The current in the primary is
|
(a) 15 A |
(b) 50 A |
(c) 25 A |
(d) 12.5 A |
When the P end of P-N junction is connected to the negative terminal of the battery and the N end to the positive terminal of the battery, then the P-N junction behaves like
|
(a) A conductor |
(b) An insulator |
(c) A super-conductor |
(d) A semi-conductor |
The graph between wave number (
) and angular frequency (w) is
|
(a)
|
(b)
|
(c)
|
(d)
|
Solar energy is mainly caused due to
|
(a) Fission of uranium present in the sun |
|
(b) Fusion of protons during synthesis of heavier elements |
|
(c) Gravitational contraction |
|
(d) Burning of hydrogen in the oxygen |
Two charges are at a distance ‘d’ apart. If a copper plate (conducting medium) of thickness 
is placed between them, the effective force will be
|
(a) 2F |
(b) F / 2 |
(c) 0 |
(d) |
