Explanation:
The locus of all particles in a medium, vibrating in the same phase is called wave front.
The direction of propagation of light (ray of light) is perpendicular to the wave front.
A wave front is an imaginary surface where all particles lying on this vibrate in the same phase.
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The radio waves of frequency 300 MHz to 3000 MHz belong to
|
(a) High frequency band |
(b) Very high frequency band |
|
(c) Ultra high frequency band |
(d) Super high frequency band |
An ammeter reads upto 1 ampere. Its internal resistance is 0.81 ohm. To increase the range to 10 A the value of the required shunt is
|
(a) 0.09 W |
(b) 0.03 W |
(c) 0.3 W |
(d) 0.9 W |
The nature of binding for a crystal with alternate and evenly spaced positive and negative ions is
|
(a) Covalent |
(b) Metallic |
(c) Dipolar |
(d) Ionic |
There are 8 equal resistances R. Two are connected in parallel, such four groups are connected in series, the total resistance of the system will be
|
(a) R / 2 |
(b) 2 R |
(c) 4 R |
(d) 8 R |
The number of electrons to be put on a spherical conductor of radius 0.1m to produce an electric field of 0.036 N/C just above its surface is
|
(a) 2.7 |
(b) 2.6 |
(c) 2.5 |
(d) 2.4 |
Two unlike charges of magnitude q are separated by a distance 2d. The potential at a point midway between them is
|
(a) Zero |
(b) |
(c) |
(d) |
Electromagnetic radiation of highest frequency is
|
(a) Infrared radiations |
(b) Visible radiation |
(c) Radio waves |
(d) g-rays |
Two bar magnets of the same mass, length and breadth but magnetic moments M and 2M respectively, when placed in same position, time period is 3 sec. What will be the time period when they are placed in different position
(a) 
|
(b) 3
|
(c) 3 sec | (d) 6 sec |
