When a particle with charge \(+q\) is thrown with an initial velocity \(v\) towards another stationary change \(+Q,\) it is repelled back after reaching the nearest distance \(r\) from \(+Q.\) The closest distance that it can reach if it is thrown with an initial velocity \(2v,\) is:
1. | \(\dfrac{r}{4}\) | 2. | \(\dfrac{r}{2}\) |
3. | \(\dfrac{r}{16}\) | 4. | \(\dfrac{r}{8}\) |
1. | \(2C\) | 2. | \(\dfrac{C}{2}\) |
3. | \(4C\) | 4. | \(\dfrac{C}{4}\) |
1. | zero | 2. | \(\dfrac{-q^2}{4\pi\varepsilon_0d}\) |
3. | \(\dfrac{-q^2}{4\pi\varepsilon_0d}\Big(3-\dfrac{1}{\sqrt2}\Big)\) | 4. | \(\dfrac{-q^2}{4\pi\varepsilon_0d}\Big(6-\dfrac{1}{\sqrt2}\Big)\) |
A hollow metal sphere of radius \(R\) is given \(+Q\) charges to its outer surface. The electric potential at a distance \(\dfrac{R}{3}\) from the centre of the sphere will be:
1. \(\dfrac{1}{4\pi \varepsilon_0}\dfrac{Q}{9R}\)
2. \(\dfrac{3}{4\pi \varepsilon_0}\dfrac{Q}{R}\)
3. \(\dfrac{1}{4\pi \varepsilon_0}\dfrac{Q}{3R}\)
4. \(\dfrac{1}{4\pi \varepsilon_0}\dfrac{Q}{R}\)
1. | \(1.5\times 10^{-6}~\text{J}\) | 2. | \(4.5\times 10^{-6}~\text{J}\) |
3. | \(3.25\times 10^{-6}~\text{J}\) | 4. | \(2.25\times 10^{-6}~\text{J}\) |
1. | dependent on the material property of the sphere |
2. | more on the bigger sphere |
3. | more on the smaller sphere |
4. | equal on both the spheres |
1. | \(9~{\mu \text{F}}\) | 2. | \(2~{\mu \text{F}}\) |
3. | \(3~{\mu \text{F}}\) | 4. | \(6~{\mu \text{F}}\) |