1
AIPMT 2012 Prelims
+4
-1
Two similar coils of radius R are lying concentrically with their planes at right angles to each other. The currents flowing in them are $$I$$ and 2$$I$$, respectively. The resultant magnetic field induction at the centre will be
A
$${{\sqrt 5 {\mu _0}I} \over {2R}}$$
B
$${{\sqrt 5 {\mu _0}I} \over R}$$
C
$${{{\mu _0}I} \over {2R}}$$
D
$${{{\mu _0}I} \over R}$$
2
AIPMT 2012 Prelims
+4
-1
An alternating electric field, of frequency $$v$$, is applied across the does (radius = R) of a cyclotron that is being used to accelerate protons (mass = m). The operating magnetic field (B) used in the cyclotron and the kinetic energy (K) of the proton beam, produced by it, are given by
A
$$B = {{m\upsilon } \over e}$$  and  $$K = 2m{\pi ^2}{\upsilon ^2}{R^2}$$
B
$$B = {{2\pi m\upsilon } \over e}$$  $$K = {m^2}\pi \upsilon {R^2}$$
C
$$B = {{2\pi m\upsilon } \over e}$$  $$K = 2m{\pi ^2}{v^2}{R^2}$$
D
$$B = {{m\upsilon } \over e}$$  $$K = {m^2}\pi \upsilon {R^2}$$
3
AIPMT 2011 Mains
+4
-1
A galvanometer of resistance, G, is shunted by a resistance S ohm. To keep the main current in the circuit unchanged, the resistance to be put in series with the galvanometer is
A
$${G \over {(S + G)}}$$
B
$${{{S^2}} \over {\left( {S + G} \right)}}$$
C
$$\left( {{{SG} \over {S + G}}} \right)$$
D
$${{{G^2}} \over {(S + G)}}$$
4
AIPMT 2011 Mains
+4
-1
Charge q is uniformly spread on a thin ring of radius R. The ring rotates about its axis with a uniform frequency $$f$$ Hz. The magnitude of magnetic induction at the center of the ring is
A
$${{{\mu _0}qf} \over {2\pi R}}$$
B
$${{{\mu _0}qf} \over {2R}}$$
C
$${{{\mu _0}q} \over {2fR}}$$
D
$${{{\mu _0}q} \over {2\pi fR}}$$
NEET Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
Chemistry
Physical Chemistry
Inorganic Chemistry
Organic Chemistry
Biology
Botany
Zoology
EXAM MAP
Joint Entrance Examination