MCQ
The period of the wave will be.
- A$2.5\mu\text{s}$
- B$0.25\mu\text{s}$
- C$0.025\mu\text{s}$
- D$\text{None of these}$
✓
Answer
- $0.025\mu\text{s}$
Explanation:
Time period, $\text{T}=\frac{1}{\text{v}}$
$\text{T}=\frac{1}{40\times10^6}$
$\Rightarrow\text{T}=0.25\mu\text{s}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
The electric field lines are far apart where electric field is:
The radius of curvature of convex surface of a thin plano-convex lens is 15 cm and refractive index of its material is 1.6. The power of the lens will be
|
(a) + 1D |
(b) -2D |
(c) +3D |
(d) +4D |
A circular coil of n turns is kept in a uniform magnetic field such that the plane of the coil is perpendicular to the field. The magnetic flux associated with the coil is now $\phi$ . Now the coil is opened and made into another circular coil of twice the radius of the previous coil and kept in the same field such that the plane of the coil is perpendicular to the field. The magnetic flux associated with this coil now is:
→A moving coil galvanometer is based on the:
There is a solid sphere of radius ‘R’ having uniformly distributed charge. What is the relation between electric field ‘E’ (inside the sphere) and radius of sphere ‘R’ is
|
(a) E ∝ |
(b) E ∝ |
(c) E ∝ |
(d) E ∝ |
To obtain electrons as majority charge carriers in a semiconductor, the impurity mixed is
|
(a) Monovalent |
(b) Divalent |
(c) Trivalent |
(d) Pentavalent |
Water is flowing in streamliries motion through a tube with its axis horizontal Consider two points A and B in the tube at the same horizontal level:
- The pressures at A and B are equal for any shape of the tube.
- The pressures are never equal.
- The pressures are equal if the tube has a uniform cross section.
- The pressures may be equal even if the tube has a nonuniform cross section.
The threshold wavelength for photoelectric emission from a material is 5200 Å. Photo-electrons will be emitted when this material is illuminated with monochromatic radiation from a
|
(a) 50 watt infrared lamp |
(b) 1 watt infrared lamp |
|
(c) 50 watt ultraviolet lamp |
(d) Both (c) and (d) |
Which of the following phenomena contributes significantly to the reddish appearance of the sun at sunrise or sunset?
Can a metal be used as a medium for dielectric
|
(a) Yes |
(b) No |
(c) Depends on its shape |
(d) Depends on dielectric |