Electron revolving in circular path of radius r with speed v produced magnetic filed B at centre. Then, correct relation among v B, and r is
(a) B ∝ \(\frac{1}{v^2}\) ∝ r2
(b) B ∝ v2∝ \(\frac{1}{r^2}\)
(c) B ∝ v∝ \(\frac{1}{r^2}\)
(d) B ∝ \(\frac{1}{v}\)∝ \(\frac{1}{r^2}\)