n automobile has a vertical radio antenna 1.40 m long. The automobile travels at 30.0 km/h on a horizontal road where Earth's magnetic field is 50.0 µT, directed toward the north and downward at an angle of 65.0° below the horizontal.

(a) Specify the direction the automobile should move so as to generate the maximum motional emf in the antenna, with the top of the antenna positive relative to the bottom.

(b) Calculate the magnitude of this induced emf.
____ mV

so i know that a) would be east, but i am having a hard time doing part B.

1 answer

Go east or west.

emf= change in B A /change in time

but the area swept out is 1.4*distance/time
distance time= 30km/hr*1hr/3600sec*1000m/km=30'/3.6 m/s

emf=30e-6* (30/3.6)cos65deg