1. Consider a rod of uniform cross section ‘A’ and length ‘l’ Let ‘n’ be the number of electrons per unit volume (number density). ‘vd ’ be the drift velocity of electrons for steady current ‘I’.
Total number of electrons in the entire volume of rod =nAl
The Lorentz force on electrons,
Charge of total electrons = nA l .e
‘e’ is the charge of a single electron.
The Lorentz force on electrons,
\(\overrightarrow F=nAle(\overrightarrow V_d\times \overrightarrow B)\)
\(\overrightarrow F=nAV_de(\overrightarrow l\times \overrightarrow B)\)
\(\overrightarrow F=I(\overrightarrow l\times \overrightarrow B)\) (I = neAVd)
2.
3. Zero
F = IlxB = IlBsinθ=IlB sin0 = 0