Question

A jet plane is travelling towards west at a speed of 1800 km/h. What is the voltage difference developed between the ends of the wing having a span of 25m, if the Earth's magnetic field at the location has magnitude of 5×10-⁴ T & the dip angle is 30°.

Answer 1

$$\begin{gathered} \mathrm{Speed}\mathrm{of}\mathrm{the}\mathrm{jet}\mathrm{plane},v=1800\mathrm{km}{\mathrm{h}}^{-1}=500\mathrm{m}{\mathrm{s}}^{-1} \\ \mathrm{Wing}\mathrm{span}\mathrm{of}\mathrm{jet}\mathrm{plane},\mathit{}l=25\mathrm{m} \\ \mathrm{Earth}\text{'}\mathrm{s}\mathrm{magnetic}\mathrm{field}\mathrm{strength},B=5\times {10}^{-4}\mathrm{T} \\ \mathrm{Angle}\mathrm{of}\mathrm{dip},\delta =30° \\ \mathrm{Vertical}\mathrm{component}\mathrm{of}\mathrm{Earth}\text{'}\mathrm{s}\mathrm{magnetic}\mathrm{field}, \\ {B}_{\mathrm{v}}=B\sin \delta \\ =5\times {10}^{-4}\sin 30° \\ =2.5\times {10}^{-4}\mathrm{T} \\ \mathrm{Voltage}\mathrm{difference}\mathrm{between}\mathrm{the}\mathrm{ends}\mathrm{of}\mathrm{the}\mathrm{wings}\mathrm{can}\mathrm{be}\mathrm{calculated}\mathrm{as}: \\ e=\left(B_{\mathrm{v}}\right)\times l\times v \\ =2.5\times {10}^{-4}\times 25\times 500 \\ =3.125\mathrm{V} \\ \mathrm{Thus},\mathrm{the}\mathrm{voltage}\mathrm{difference}\mathrm{developed}\mathrm{between}\mathrm{the}\mathrm{ends}\mathrm{of}\mathrm{the}\mathrm{wing}\mathrm{is}3.125\mathrm{V} \end{gathered}$$