When a wire loop is rotated in a magnetic field, the direction of induced e.m.f. changes once in each
|
(a) |
(b) |
(c) 1 revolution |
(d) 2 revolution |
(b) 
revolution
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
The percentage of Sun's total energy which reaches the earth's surface is
|
(a) 10–7 % |
(b) 10–6 % |
(c) 10–3 % |
(d) 10–2 % |
The work function of a metal is
|
(a) The energy for the electron to enter into the metal |
|
(b) The energy for producing X-ray |
|
(c) The energy for the electron to come out from metal surface |
|
(d) None of these |
The electron in a hydrogen atom makes a transition 
, where 
and 
are the principal quantum numbers of the two states. Assume the Bohr model to be valid. The time period of the electron in the initial state is eight times that in the final state. The possible values of n1 and n2 are
|
(a) |
(b) |
(c) |
(d) |
The idea of the quantum nature of light has emerged in an attempt to explain
|
(a) Interference |
(b) Diffraction |
|
(c) Radiation spectrum of a black body |
(d) Polarisation |
The electrical circuit used to get smooth dc output from a rectifier circuit is called
| (a) Oscillator | (b) Filter | (c) Amplifier | (d) Logic gates |
What is the ratio of heat generated in R and 2R
|
(a) 2 : 1 |
(b) 1 : 2 |
(c) 4 : 1 |
(d) 1 : 4 |
