The wing span of an aeroplane is 40m. The plane is flying horizontally due north at 360 km/h. What is the potential difference developed between the wing-tips if the horizontla component of the Earth's magnetic field `B_(h) = 3.2 xx 10^(-5)`T and the angle of dip at the place is `60^(@)` ?

Explanation

Data: l=40m, v=360 km/h `=360 xx 5/18= 100` m/s,
`B_(h) = 3.2 xx 10^(-5) T, delta = 60^(@)`
The area swept out by the wing per unit time= lv.
The magnetic lines of induction perpendicular to this area are those of the vertical component `B_(v)` of the Earth's magnetic field.
`B_(v) = B_(h) tan delta`
where `delta` is the angle of dip.
`therefore` The magnetic flux cut by the wing per unit time
`=(dPhi_(m))/(dt) = B_(v)(lv) = B_(h)tan delta(lv)`
`=(3.2 xx 10^(-5))(tan 60^(@))(40)(100)`
`=(12.8 xx 10^(-2))(1.732) = 0.2217 Wb//s`
`therefore` The induced emf, `E=-(dPhi_(m))/(dt)` (nummerically)
`=0.2217` V