A hollow conducting sphere is placed in an electric field produced by a point charge placed at P as shown in the figure. Let\(V_A ~,V_B~,V_C\) be the potentials at points A, B and C respectively. Then:
1. \(V_A<V_B<V_C\)
2. \(V_A>V_B>V_C\)
3. \(V_C>V_B=V_A\)
4. \(V_A=V_B=V_C\)
Four particles each having charge q are placed at the vertices of a square of side a. The value of the electric potential at the midpoint of one of the side will be
1. 0
2.
3.
4.
The electric potential at the surface of a charged solid sphere of insulator is 20V. The value of electric potential at its centre will be
1. 30V
2. 20V
3. 40V
4. Zero
The electric potential at a point at distance 'r' from a short dipole is proportional to
(1)
(2)
(3)
(4)
A hollow charged metal spherical shell has radius R. If the potential difference between its surface and a point at a distance 3R from the center is V, then the value of electric field intensity at a point at distance 4R from the center is
1.
2.
3.
4.
Two metallic spheres of radii 2cm and 3cm are given charges 6mC and 4mC respectively. The final charge on the smaller sphere will be if they are connected by a conducting wire
(1) 4mC
(2) 6mC
(3) 5mC
(4) 10mC
When a proton at rest is accelerated by a potential difference \(V\), its speed is found to be \(v\). The speed of an \(\alpha-\textit{particle}\) when accelerated by the same potential difference from rest will be:
1. | \(V\) | 2. | \(v \over \sqrt{2}\) |
3. | \(v \sqrt{2}\) | 4. | \(2V\) |
A and B are two concentric metallic shells. If A is positively charged and B is earthed, then electric
1. Field at common centre is non-zero
2. Field outside B is nonzero
3. Potential outside B is positive
4. Potential at common centre is positive
Two spheres of radius a and b respectively are charged and joined by a wire. The ratio of the electric field at the surface of the spheres is
(1) a/b
(2) b/a
(3) a2/b2
(4) b2/a2