The figure shows the electric lines of force emerging from a charged body. If the electric field at \(A\) and \(B\) are \(E_A\) and \(E_B\) respectively and if the displacement between \(A\) and \(B\) is \(r,\) then:
1. \(E_A>E_B\)
2. \(E_A<E_B\)
3. \(E_{A} = \frac{E_{B}}{r}\)
4. \(E_{A} = \frac{E_{B}}{r^{2}}\)
A thin conducting ring of the radius \(R\) is given a charge \(+Q.\) The electric field at the centre \(O\) of the ring due to the charge on the part \(AKB\) of the ring is \(E.\) The electric field at the centre due to the charge on the part \(ACDB\) of the ring is:
1. | \(3E\) along \(KO\) |
2. | \(E\) along \(OK\) |
3. | \(E\) along \(KO\) |
4. | \(3E\) along \(OK\) |
A charged particle \(q\) of mass \(m\) is released on the \(y\text-\)axis at \(y=a\) in an electric field \(\vec E = -4y \hat{j}.\) The speed of the particle on reaching the origin will be:
1. \(\sqrt{\frac{2 a}{m q}}\)
2. \(\frac{a}{\sqrt{m q}}\)
3. \(2 a \sqrt{\frac{q}{m}}\)
4. \(2 \sqrt{\frac{a}{m q}}\)
Three identical positive point charges, as shown are placed at the vertices of an isosceles right-angled triangle. Which of the numbered vectors coincides in direction with the electric field at the mid-point \(M\) of the hypotenuse?
1. \(1\)
2. \(2\)
3. \(3\)
4. \(4\)
A metallic solid sphere is placed in a uniform electric field. The lines of force, as shown in the figure, follow the path(s):
1. \(1\)
2. \(2\)
3. \(3\)
4. \(4\)
A charge \(q\) is placed in a uniform electric field \(E.\) If it is released, then the kinetic energy of the charge after travelling distance \(y\) will be:
1. | \(qEy\) | 2. | \(2qEy\) |
3. | 4. |
The electrostatic field due to a charged conductor just outside the conductor is:
1. | zero and parallel to the surface at every point inside the conductor. |
2. | zero and is normal to the surface at every point inside the conductor. |
3. | parallel to the surface at every point and zero inside the conductor. |
4. | normal to the surface at every point and zero inside the conductor. |
1. | ![]() |
2. | ![]() |
3. | ![]() |
4. | ![]() |
Two-point charges \(+8q\) and \(-2q\) are located at \(x=0\) and \(x=L\) respectively. The location of a point on the \(x\text-\)axis at which the net electric field due to these two point charges is zero is:
1. \(8L\)
2. \(4L\)
3. \(2L\)
4. \(\frac{L}{4}\)
A spherical conductor of radius \(10~\text{cm}\) has a charge of \(3.2 \times 10^{-7}~\text{C}\) distributed uniformly. What is the magnitude of the electric field at a point \(15~\text{cm}\) from the centre of the sphere?
\(\left(\frac{1}{4\pi \varepsilon _0} = 9\times 10^9~\text{N-m}^2/\text{C}^2\right)\)
1. \(1.28\times 10^{5}~\text{N/C}\)
2. \(1.28\times 10^{6}~\text{N/C}\)
3. \(1.28\times 10^{7}~\text{N/C}\)
4. \(1.28\times 10^{4}~\text{N/C}\)