- AAre not imaginary lines.
- BCannot be mapped on paper.
- CDo not intersect each other.
- DAlways intersect each other.
Explanation:
lines of force do not intersect each other because at the point of intersection we will have two different direction of the force, as their will be two tangential direction corresponding to the two intersecting lines.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
A solenoid has an inductance of 60 henrys and a resistance of 30 ohms. If it is connected to a 100 volt battery, how long will it take for the current to reach
of its final value
|
(a) 1 second |
(b) 2 seconds |
(c) e seconds |
(d) 2e seconds |
A long wire AB is placed on a table. Another wire PQ of mass 1.0 g and length 50 cm is set to slide on two rails PS and QR. A current of 50A is passed through the wires. At what distance above AB, will the wire PQ be in equilibrium
|
(a) 25 mm |
(b) 50 mm |
(c) 75 mm |
(d) 100 mm |
A thin prism P1 with angle 4° and made from glass of refractive index 1.54 is combined with another thin prism P2 made from glass of refractive index 1.72 to produce dispersion without deviation. The angle of prism P2 is
|
(a) 2.6° |
(b) 3° |
(c) 4° |
(d) 5.33° |
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 |
An electron (charge = 1.6
coulomb) is accelerated through a potential of 1,00,000 volts. The energy required by the electron is
|
(a) 1.6 |
(b) 1.6 |
(c) 0.53 |
(d) 1.6 |
Two thin lenses, one of focal length + 60 cm and the other of focal length – 20 cm are put in contact. The combined focal length is
|
(a) + 15 cm |
(b) – 15 cm |
(c) + 30 cm |
(d) –30 cm |