The electric field of an electromagnetic wave in free space is given by $$\overrightarrow E = 10\cos ({10^7}t + kx)\widehat j\,\,V/m,$$ where t and x are in seconds and metres respectively. It can be inferred that
(1) the wavelength $$\lambda $$ is 188.4 m.
(2) the wave number k is 0.33 rad/m.
(3) the wave amplitude is 10 V/m.
(4) the wave is propagating along +x direction.
Which one of the following pairs of statements is correct ?
A
(3) and (4)
B
(1) and (2)
C
(2) and (3)
D
(1) and (3)
2
AIPMT 2010 Mains
MCQ (Single Correct Answer)
+4
-1
A condenser of capacity C is charged to a potential difference of V1. The plates of th condenser are then connected to an ideal inductor of inductance L. The current through the inductor when the potential difference across the condenser reduces to V2 is
A current loop consists of two identical semicircular parts each of radius R, one lying in the x-y plane and the other in x-z plane. If the current in the loop is $$i$$. The resultant magnetic field due to the two semicircular parts at their common centre is
A
$${{{\mu _0}i} \over {2\sqrt 2 R}}$$
B
$${{{\mu _0}i} \over {2R}}$$
C
$${{{\mu _0}i} \over {4R}}$$
D
$${{{\mu _0}i} \over {\sqrt 2 R}}$$
4
AIPMT 2010 Mains
MCQ (Single Correct Answer)
+4
-1
Two identical bar magnets are fixed with their centers at a distance d apart. A stationary charge Q is placed at P in between the gap of the two magnets at a distance D from the centre O as shown in the figure
