- AIn same phase
- BIn opposite phase
- CUp and down
- DLeft and right
Explanation:
Wave front by definition is the locus of points having same phase.
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Vibration magnetometer before use, should be set
| (a) In magnetic meridian | (b) In geographical meridian |
| (c) Perpendicular to magnetic meridian | (d) In any position |
At room temperature, a P-type semiconductor has
|
(a) Large number of holes and few electrons |
|
(b) Large number of free electrons and few holes |
|
(c) Equal number of free electrons and holes |
|
(d) No electrons or holes |
Television signals broadcast from the moon can be received on the earth while the TV broadcast from Delhi cannot be received at places about 100 km distant from Delhi. This is because
|
(a) There is no atmosphere around the moon |
|
(b) Of strong gravity effect on TV signals |
|
(c) TV signals travel straight and cannot follow the curvature of the earth |
|
(d) There is atmosphere around the earth |
Some electric bulbs are connected in series across a 220 V supply in a room. If one bulb is fused then remaining bulbs are connected again in series across the same supply. The illumination in the room will
|
(a) Increase |
(b) Decrease |
(c) Remains the same |
(d) Not continuous |