In a dc motor, induced e.m.f. will be maximum
|
(a) When motor takes maximum speed |
(b) When motor starts rotating |
|
(c) When speed of motor increases |
(d) When motor is switched off |
(a) When motor takes maximum speed
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
The phenomenon of diffraction of light was discovered by
|
(a) Hygens |
(b) Newton |
(c) Fresnel |
(d) Grimaldi |
Focal length of a convex lens will be maximum for
|
(a) Blue light |
(b) Yellow light |
(c) Green light |
(d) Red light |
Unit of magnetic flux density (or magnetic induction) is
| (a) Tesla | (b) Weber/metre2 |
| (c) Newton/ampere-metre | (d) All of the above |
The current carrying wire and the rod AB are in the same plane. The rod moves parallel to the wire with a velocity v. Which one of the following statements is true about induced emf in the rod
|
(a) End A will be at lower potential with respect to B |
|
(b) A and B will be at the same potential |
|
(c) There will be no induced e.m.f. in the rod |
|
(d) Potential at A will be higher than that at B |
Wavefront means
|
(a) All particles in it have same phase |
|
(b) All particles have opposite phase of vibrations(c) Few particles are in same phase, rest are in opposite phase |
|
(c) Few particles are in same phase, rest are in opposite phase |
|
(d) None of these |
An artificial radioactive decay series begins with unstable 
. The stable nuclide obtained after eight α - decays and five β- decays is
|
(a) |
(b) |
(c) |
(d) |
In comparison to a half wave rectifier, the full wave rectifier gives lower
|
(a) Efficiency |
(b) Average dc |
|
(c) Average output voltage |
(d) None of these |
The image which can be obtained on a screen is called:
