A horizontal straight wire $5 \mathrm{m}$ long extending from east to west falling freely at right angle to horizontal component of earth's magnetic field $0.60\times {10}^{-4} \mathrm{Wb} {\mathrm{m}}^{-2}$. The instantaneous value of emf induced in the wire when its velocity is $10 \mathrm{m} {\mathrm{s}}^{-1}$ is _______$\times {10}^{-3} \mathrm{V}$.