Question

Conductor of length T moves perpendicular to its length with the speed V. Length of the conductor is perpendicular to the magnetic field of the conductor. Let us assume that electrons could move freely in the conductor and the charge of an electron is ‘e’.

a) What is the magnetic force acting on electron in the conductor? 

b) In which direction does the above force act? 

c) What effect does this force have on motion of electrons?

Answer 1

a) Magnetic field acting on the electron inside the conductor is = F_m = e (V¯ × B)= BeV

This field acts from P to Q.

b) Consider in the field P and Q are ends of a conductor. ‘Q’ will act as negative end and ‘P’ will act as positive end then flow passes from P to Q means downwards. 

c) The force on electrons shows an effect creates a potential difference at the ends of the rods. 

∴ BeV = eE ⇒ E = BY