Microscope is an optical instrument which
|
(a) Enlarges the object |
|
(b) Increases the visual angle formed by the object at the eye |
|
(c) Decreases the visual angle formed by the object at the eye |
|
(d) Brings the object nearer |
(b) Increases the visual angle formed by the object at the eye
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Two thin lenses of focal lengths f1 and f2 are in contact. The focal length of this combination is
|
(a) |
(b) |
(c) |
(d) |
For comparing the e.m.f.'s of two cells with a potentiometer, a standard cell is used to develop a potential gradient along the wires. Which of the following possibilities would make the experiment unsuccessful
|
(a) The e.m.f. of the standard cell is larger than the E e.m.f.'s of the two cells |
|
(b) The diameter of the wires is the same and uniform throughout |
|
(c) The number of wires is ten |
|
(d) The e.m.f. of the standard cell is smaller than the e.m.f.'s of the two cells |
The critical angle of a material is the angle of incidence for which the angle of refraction is:
Two infinitely long parallel conducting plates having surface charge densities +σ and -σ respectively, are separated by a small distance. The medium between the plates is vacuum. If 
is the dielectric permittivity of vacuum, then the electric field in the region between the plates is
|
(a) 0 volts/meter |
(b) |
(c) |
(d) |
What is the stopping potential when the metal with work function 0.6 eV is illuminated with the light of 2 eV
|
(a) 2.6 V |
(b) 3.6 V |
(c) 0.8 V |
(d) 1.4 V |
When the current in a coil changes from 8 ampere to 2 ampere in 3 
second, the e.m.f. induced in the coil is 2 volt. The self inductance of the coil (in millihenry) is
|
(a) 1 |
(b) 5 |
(c) 20 |
(d) 10 |
A long solenoid has n turns per meter and current I A is flowing through it. The magnetic field at the ends of the solenoid is
|
(a) |
(b) |
(c) Zero |
(d) 2 |
