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An aeroplane is flying horizontally from west to east with a velocity of 900 km/hour. Calculate the potential difference developed between the ends of its wings having a span of 20 m. The horizontal component of the Earth's magnetic field is 5 × 10–4 T and the angle of dip is 30°.
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Potential difference developed between the ends of the wings e = BlЁЭЬИ
Given Velocity v = 900km/hour = 250m/s
The horizontal component of the Earth’s magnetic field = 5× 10-4T
Wing span (l) = 20 m
The vertical component of Earth’s magnetic field
BV = BH tan δ
= 5×10−4 (tan 30° ) T
∴ The potential difference, e
= 5×10−4 ( tan 30° ) × 20 × 250
e = `(5 xx 10^-4 xx 20 xx 250)/sqrt3 = 1.44 "V"`
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