If \(50~\text{J}\) of work must be done to move an electric charge of \(2~\text{C}\) from a point where the potential is \(-10\) volt to another point where the potential is \(\mathrm{V}\) volt, then the value of \(\mathrm{V}\) is:
1. \(5\) volt
2. \(-15\) volt
3. \(+15\) volt
4. \(+10\) volt
Three charges, each \(+q\), are placed at the corners of an equilateral triangle \(ABC\) of sides \(BC\), \(AC\), and \(AB\). \(D\) and \(E\) are the mid-points of \(BC\) and \(CA\). The work done in taking a charge \(Q\) from \(D\) to \(E\) is:
1. | \(\frac{3qQ}{4\pi \varepsilon_0 a}\) | 2. | \(\frac{3qQ}{8\pi \varepsilon_0 a}\) |
3. | \(\frac{qQ}{4\pi \varepsilon_0 a}\) | 4. | \(\text{zero}\) |
A bullet of mass 2 g is having a charge of 2 µC. Through what potential difference must it be accelerated, starting from rest, to acquire a speed of 10 m/s?
1. 50 kV
2. 5 V
3. 50 V
4. 5 kV
Ten electrons are equally spaced and fixed around a circle of radius R. Relative to V = 0 at infinity, the electrostatic potential V and the electric field E at the centre C are:
1. | \(V \neq 0 \text { and } \vec{E} \neq 0\) |
2. | \(V \neq 0 \text { and } \vec{E}=0\) |
3. | \(V=0 \text { and } \vec{E}=0\) |
4. | \(V=0 \text { and } \vec{E} \neq 0\) |
Four electric charges \(+\mathrm q,\) \(+\mathrm q,\) \(-\mathrm q\) and \(-\mathrm q\) are placed at the corners of a square of side \(2\mathrm{L}\) (see figure). The electric potential at point A, mid-way between the two charges \(+\mathrm q\) and \(+\mathrm q\) is:
1.
2.
3. zero
4.
Eight equally charged tiny drops are combined to form a big drop. If the potential on each drop is 10 V, then the potential of the big drop will be:
1. | 40 V | 2. | 10 V |
3. | 30 V | 4. | 20 V |
The increasing order of the electrostatic potential energies for the given system of charges is given by:
1. | a = d < b < c | 2. | b = d < c < a |
3. | b = c < a < d | 4. | c < a < b < d |
In the figure the charge Q is at the centre of the circle. Work done by the conservative force is maximum when another charge is taken from point P to:
1. | K | 2. | L |
3. | M | 4. | N |
Two equal charges q of opposite sign separated by a distance 2a constitute an electric dipole of dipole moment p. If P is a point at a distance r from the centre of the dipole and the line joining the centre of the dipole to this point makes an angle θ with the axis of the dipole, then the potential at P is given by: (r >> 2a) (Where p = 2qa)
1. | \(V={pcos \theta \over 4 \pi \varepsilon_0r^2}\) | 2. | \(V={pcos \theta \over 4 \pi \varepsilon_0r}\) |
3. | \(V={psin \theta \over 4 \pi \varepsilon_0r}\) | 4. | \(V={pcos \theta \over 2 \pi \varepsilon_0r^2}\) |
The variation of electrostatic potential with radial distance \(r\) from the centre of a positively charged metallic thin shell of radius \(R\) is given by the graph:
1. | 2. | ||
3. | 4. |