1
AIEEE 2004
+4
-1
A coil having $$n$$ turns and resistance $$R\Omega$$ is connected with a galvanometer of resistance $$4R\Omega .$$ This combination is moved in time $$t$$ seconds from a magnetic field $${W_1}$$ weber to $${W_2}$$ weber. The induced current in the circuit is
A
$${{\left( {{W_2} - {W_1}} \right)} \over {Rnt}}$$
B
$$- {{n\left( {{W_2} - {W_1}} \right)} \over {5\,\,Rt}}$$
C
$$- {{\left( {{W_2} - {W_1}} \right)} \over {5\,\,Rnt}}$$
D
$$- {{n\left( {{W_2} - {W_1}} \right)} \over {Rt}}$$
2
AIEEE 2004
+4
-1
In a uniform magnetic field of induction $$B$$ a wire in the form of a semicircle of radius $$r$$ rotates about the diameter of the circle with an angular frequency $$\omega .$$ The axis of rotation is perpendicular to the field. If the total resistance of the circuit is $$R,$$ the mean power generated per period of rotation is
A
$${{{{\left( {B\pi r\omega } \right)}^2}} \over {2R}}$$
B
$${{{{\left( {B\pi {r^2}\omega } \right)}^2}} \over {8R}}$$
C
$${{B\pi {r^2}\omega } \over {2R}}$$
D
$${{{{\left( {B\pi r{\omega ^2}} \right)}^2}} \over {8R}}$$
3
AIEEE 2004
+4
-1
A metal conductor of length $$1$$ $$m$$ rotates vertically about one of its ends at angular velocity $$5$$ radians per second. If the horizontal component of earth's magnetic field is $$0.2 \times {10^{ - 4}}T,$$ then the $$e.m.f.$$ developed between the two ends of the conductor is
A
$$5mV$$
B
$$50\mu V$$
C
$$5\mu V$$
D
$$50mV$$
4
AIEEE 2003
+4
-1
Two coils are placed close to each other. The mutual inductance of the pair of coils depends upon
A
the rates at which currents are changing in the two coils
B
relative position and orientation of the two coils
C
the currents in the two coils
D
the materials of the wires of the coils
EXAM MAP
Medical
NEETAIIMS