Earth's magnetism

A metallic conductor of length 1 m rotates in a vertical plane parallel to east-west direction about one of its end with angular velocity 5 rad s$^{-1}$. If the horizontal component of earth's magnetic field is $0.2\times10^{-4}$ T, then emf induced between the two ends of the conductor is :

A metallic rod of length 20 cm is placed in North-South direction and is moved at a constant speed of 20 m/s towards East. The horizontal component of the Earth's magnetic field at that place is $4\times10^{-3}$ T and the angle of dip is 45°. The emf induced in the rod is ______ mV.

At a certain place the angle of dip is 30° and the horizontal component of earth's magnetic field is 0.5 G. The earth's total magnetic field (in G), at that certain place, is :

A magnet hung at 45° with magnetic meridian makes an angle of 60° with the horizontal. The actual value of the angle of dip is -

A compass needle of oscillation magnetometer oscillates 20 times per minute at a place P of dip 30°. The number of oscillations per minute become 10 at another place Q of 60° dip. The ratio of the total magnetic field at the two places $(B_Q:B_P)$ is :

The vertical component of the earth's magnetic field is $6\times10^{-5}$ T at any place where the angle of dip is 37°. The earth's resultant magnetic field at that place will be (Given tan 37° = $\frac34$)

A fighter plane of length 20 m, wing span (distance from tip of one wing to the tip of the other wing) of 15 m and height 5 m is flying towards east over Delhi. Its speed is 240 ms$^{-1}$. The earth's magnetic field over Delhi is $5\times10^{-5}$ T with the declination angle ~0° and dip of θ such that $\sin\theta=\dfrac23$. If the voltage developed is $V_B$ between the lower and upper side of the plane and $V_W$ between the tips of the wings then $V_B$ and $V_W$ are close to :

A short bar magnet is placed in the magnetic meridian of the earth with north pole pointing north. Neutral points are found at a distance of 30 cm from the magnet on the East - West line, drawn through the middle point of the magnet. The magnetic moment of the magnet in Am$^2$ is close to :

(Given $\dfrac{\mu_0}{4\pi}=10^{-7}$ in SI units and $B_H$ = Horizontal component of earth's magnetic field = $3.6\times10^{-5}$ Tesla.)

The magnetic field of earth at the equator is approximately $4\times10^{-5}$ T. The radius of earth is $6.4\times10^6$ m. Then the dipole moment of the earth will be nearly of the order of :