A positive charge Qis uniformly distributed along a circular ring of radius R. A small test charge q is placed at the centre of the ring as shown in figure. Then
(a) If q>0 and is displaced away from the centre in the plane of the ring it will be pushed back towards the centre
(b) If q<0 and is displaced away from the centre in the plane of the ring, it will never return to the centre an will continue moving till it hits the ring
(c) If q<0 , it will perform SHM for small displacement along the axis.
(d) Q at the centre of the ring is in an unstable equilibrium within the plalne of the ring for q>O
This is a Multiple Choice Questions as classified in NCERT Exemplar
Answer- a, b, c
Explanation- the positive charge Q is uniformly distributed at the outer surface of the enclosed sphere thus electric field inside the sphere is zero. So the effect of electric field on charge q due to positive charge Q is zero.
Now the only attractive and repulsive force between Q and q
Case 1 q>0 this creates repulsive force
Case 2 q<0 this creates attractive force
If q is shifted from the centre then the positive charges nearer to this charge will attract it towards itself and charge q will never return to its centre.
<p>This is a Multiple Choice Questions as classified in NCERT Exemplar</p><p>Answer- a, b, c</p><p>Explanation- the positive charge Q is uniformly distributed at the outer surface of the enclosed sphere thus electric field inside the sphere is zero. So the effect of electric field on charge q due to positive charge Q is zero.</p><p>Now the only attractive and repulsive force between Q and q</p><p>Case 1 q>0 this creates repulsive force</p><p>Case 2 q<0 this creates attractive force</p><p> If q is shifted from the centre then the positive charges nearer to this charge will attract it towards itself and charge q will never return to its centre.</p>
The following are the topics covered in this chapter: Electric Field and Field Lines, Gauss's Law, Electric Dipole, Conductors and Insulators, and Electric Flux.
Indeed, it is an easy chapter of Class 12 Physics. In this chapter, you will learn about the foundational concepts like Gauss's law and electric fields.
In the medical entrance test NEET, this chapter has a moderate weightage. You can expect around 2-3 questions of this chapter that contributes to the 3-5% of the total marks in the Physics section.
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