An aircraft with a wingspan of $40 \mathrm{m}$ files with a speed of $1080 \mathrm{km} {\mathrm{hr}}^{-1}$ in the eastward direction at a constant altitude in the northern-hemisphere, where the vertical component of the earth's magnetic field $1.75\times {10}^{-5} \mathrm{T}$. Then the emf developed between the tips of the wings is

A horizontal rod of length $L$ rotates about a vertical axis with a uniform angular velocity $\mathrm{\omega }$. A uniform magnetic field $B$ exists parallel to the axis of rotation. Then potential difference between the two ends of the rod is

A constant force $F$ is being applied on a rod of length $l$ kept at rest on two parallel conducting rails connected at ends by resistance $R$ in uniform magnetic field $B$ as shown,

Figure shows a square loop of side $1 \mathrm{m}$ and resistance $1 \mathrm{\Omega }$. The magnetic field on left side of line $PQ$ has a magnitude $B=1.0 \mathrm{T}$. The work done in pulling the loop out of the field uniformly in $1 \mathrm{s}$ is,

A conducting rod $AB$ of length $l=1 \mathrm{m}$ is moving at a velocity $v=4 \mathrm{m} {\mathrm{s}}^{-1}$ making an angle $30°$ with its length. A uniform magnetic field $B=2 \mathrm{T}$ exists in a direction perpendicular to the plane of motion. Then

A metallic square wire frame $ABCD$ of side a is moving with a constant velocity $v$ in a uniform magnetic field $B$ as shown. The emf induced between points $A$ and $C$ is: