- ACathode ray oscilloscope
- BFluorescent tube
- CX-ray tube
- DAll the above
Explanation:
A discharge tube is a tube containing charged electrodes and filled with a gas in which ionization is induced by an electric filed. X-ray tube, fluroscent tube and cathode rays oscilloscope can be used as a modified discharge tube in which these tubes contain charged electrodes and filled with a gas.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
In hydrogen atom, an electron is revolving in the orbit of radius 0.53
with 6.6
rotations/second. Magnetic field produced at the centre of the orbit is
|
(a) 0.125 |
(b) 1.25 |
(c) 12.5 |
(d) 125 |
Three resistors are connected to form the sides of a triangle ABC, the resistance of the sides AB, BC and CA are 40 ohms, 60 ohms and 100 ohms respectively. The effective resistance between the points A and B in ohms will be
|
(a) 32 |
(b) 64 |
(c) 50 |
(d) 200 |
A parallel plate capacitor of capacity is charged to a potential
(i) The energy stored in the capacitor when the battery is disconnected and the separation is doubled
(ii) The energy stored in the capacitor when the charging battery is kept connected and the separation between the capacitor plates is doubled is Then
value is
|
(a) 4 |
(b) 3/2 |
(c) 2 |
(d) 1/2 |
By a cell a current of 0.9 A flows through 2 ohm resistor and 0.3 A through 7 ohm resistor. The internal resistance of the cell is
|
(a) 0.5 Ω |
(b) 1.0 Ω |
(c) 1.2 Ω |
(d) 2.0 Ω |
Magnetic dipole moment of a rectangular loop is
|
(a) Inversely proportional to current in loop |
|
(b) Inversely proportional to area of loop |
|
(c) Parallel to plane of loop and proportional to area of loop |
|
(d) Perpendicular to plane of loop and proportional to area of loop |
An X-ray tube is operated at 50 kV. The minimum wavelength produced is
| (a) 0.5 Å | (b) 0.75 Å | (c) 0.25 Å | (d) 1 Å |
Two circular coils can be arranged in any of the three situations shown in the figure. Their mutual inductance will be

|
(a) Maximum in situation (A) |
(b) Maximum in situation (B) |
|
(c) Maximum in situation (C) |
(d) The same in all situations |
Consider the following statements A to B and identify the correct answer
A. Polarised light can be used to study the helical surface of nucleic acids.
B. Optics axis is a direction and not any particular line in the crystal
|
(a) A and B are correct |
(b) A and B are wrong |
|
(c) A is correct but B is wrong |
(d) A is wrong but B is correct |