- ANAND.
- BNOR.
- CAND.
- DOR.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
In Cu-Fe couple, the flow of current at the temperature of inversion is
|
(a) From Fe to Cu through the hot junction |
|
(b) From Cu to Fe through the hot junction |
|
(c) Maximum |
|
(d) None of the above |
If a magnet of pole strength m is divided into four parts such that the length and width of each part is half that of initial one, then the pole strength of each part will be
|
(a) m/4 |
(b) m/2 |
(c) m/8 |
(d) 4m |
Assertion : An N-type semiconductor has a large number of electrons but still it is electrically neutral.
Reason : An N-type semiconductor is obtained by doping an intrinsic semiconductor with a pentavalent impurity.
|
(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
|
(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
|
(c) If assertion is true but reason is false. |
|
(d) If the assertion and reason both are false. |
X-rays are in nature similar to
| (a) Beta rays | (b) Gamma rays | (c) de-Broglie waves | (d) Cathode rays |
The ratio of de-Broglie wavelengths of molecules of hydrogen and helium which are at temperature 27oC and 127oC respectively is
|
(a) |
(b) |
(c) |
(d) 1 |
The graph which represents the correct variation of logarithm of activity (log A) versus time, in figure is

|
(a) A |
(b) B |
(c) C |
(d) D |
The difference in the variation of resistance with temperature in a metal and a semiconductor arises essentially due to the difference in the
|
(a) Variation of scattering mechanism with temperature |
|
(b) Crystal structure |
|
(c) Variation of the number of charge carriers with temperature |
|
(d) Type of bon |
If q is the charge per unit area on the surface of a conductor, then the electric field intensity at a point on the surface is
|
(a) |
(b) |
|
(c) |
(d) |
A rocket is going towards moon with a speed v. The astronaut in the rocket sends signals of frequency v towards the moon and receives them back on reflection from the moon. What will be the frequency of the signal received by the astronaut (Take v << c)
|
(a) |
(b) |
(c) |
(d) |