(a)i State the condition for a charged particle to experience a force in magnetic field

(ii) State the expression for the magnetic force, F acting on a charged particle, Q in a magnetic field of flux density, \(\beta\) with speed, V

(iii) Prove quantitatively that there is no magnetic force moving along the direction of a magnetic field.

(b)i Mention the main parts of an electrical transformer.

(ii) Explain how an alternating potential difference applied to the primary coil gives rise to an induced e.m.f in the secondary coil of a transformer.

(c) Proton of mass 1.7 x 10(^{-27}\) kg enters a magnetic field of flux density 0.207 normally and followed a quarter circle path before existing with a constant speed of 4.5 x 10\(^6\)m/s

(i) Explain why the speed of the proton remains constant.

(ii) Calculate the 

I. radius of the circular path

II. time taken by the proton to move through the magnetic field [e = 1.6 x 10\(^{-19}\) C, \(\pi\) = 3.14]