An aircraft with a wingspan of 40 m flies with a speed of 1080 km h–1 in the eastward direction at a constant altitude in the northern hemisphere, where the vertical component of earth's magnetic field is 1.75 x 10–5 T. Then the e.m.f. that develops between the tips of the wings is

0.5V 0.34V 0.21V 2.1V

0.21V

$\xi = Blv $ $v = 1080km/h = 300m/s , B = 1.75 times 10^{-5} T , L = 40m$ $ \Rightarrow \xi = 0.21V$