Which of the following particles will experience maximum magnetic force (magnitude) when projected with the same velocity perpendicular to a magnetic field?
1. electron
2. proton
3. He⁺
4. Li⁺⁺

Which of the following particles will describe the smallest circle when projected with the same velocity perpendicular to a magnetic field?

1.   Electron

2.   Proton

3.   He⁺

4.   Li⁺

Which of the following particles will have minimum frequency of revolution when projected with the same velocity perpendicular to a magnetic field?
1. electron
2. proton
3. He⁺
4. Li⁺

A circular loop of area \(1\) cm², carrying a current of \(10\) A, is placed in a magnetic field of \(0.1\) T perpendicular to the plane of the loop. The torque on the loop due to the magnetic field is:
1. zero
2. \(10^{-4}\) N-m
3. \(10^{-2}\) N-m
4. \(1\) N-m

A beam consisting of protons and electrons moving at the same speed goes through a thin region in which there is a magnetic field perpendicular to the beam. The protons and the electrons,

A charged particle moves in a uniform magnetic field. The velocity of the particle at some instant makes an acute angle with the magnetic field. The path of the particle will be

1.  a straight line

2.  a circle

3.  a helix with uniform pitch

4.  a helix with a nonuniform pitch

A particle moves in a region having a uniform magnetic field and a parallel, uniform electric field. At some instant, the velocity of the particle is perpendicular to the field direction. The path of the particle will be 

1.  a straight line

2.  a circle 

3.  a helix with uniform pitch 

4.  a helix with a nonuniform pitch

An electric current \(i\) enters and leaves a uniform circular wire of radius \(a\) through diametrically opposite points. A charged particle \(q\) moving along the axis of the circular wire passes through its centre at speed \(v\). The magnetic force acting on the particle when it passes through the centre has a magnitude:
1. \(qv\frac{\mu_{0} {i}}{2 {a}}m\)
2. \(qv\frac{\mu_{0} {i}}{2 {\pi a}}\)
3. \(qv\frac{\mu_{0}{i}}{ {a}}\)
4. zero

If a charged particle at rest experiences no electromagnetic force then,

If a charged particle kept at rest experiences an electromagnetic force,

Choose the correct option: 
1. (a), (b)
2. (b), (c)
3. (c), (d)
4. (a), (d)