Six charges \(+q,\) \(-q,\) \(+q,\) \(-q,\) \(+q\) and \(-q\) are fixed at the corners of a hexagon of side \(d\) as shown in the figure. The work done in bringing a charge \(q_0\) to the centre of the hexagon from infinity is: (\(\varepsilon_0\text-\)permittivity of free space)
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. \(\dfrac{-q^2}{4\pi\varepsilon_0d}\Big(6-\dfrac{1}{\sqrt2}\Big)\)
Subtopic:  Electric Potential Energy |
 85%
Level 1: 80%+
NEET - 2022
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A positively charged particle \(+q\) is projected with speed \(v\) toward a fixed charge \(+Q,\) and rebounds after reaching a minimum distance \(r.\) What will be the new closest distance of approach if its initial velocity is doubled to \(2v\text{?}\)

1. \(\dfrac{r}{4}\) 2. \(\dfrac{r}{2}\)
3. \(\dfrac{r}{16}\) 4. \(\dfrac{r}{8}\)
Subtopic:  Electric Potential Energy |
 72%
Level 2: 60%+
NEET - 2022
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The value of the electric potential at a distance of \(9~\text{cm}\) from the point charge \(4\times10^{-7}~\text{C}\) is:
\(\left[\mathrm{Given}\dfrac{1}{4\pi\varepsilon_{0}}=9\times10^{9}~\text{N m}^{2}~\text{C}^{-2}\right]\)
1. \(4\times10^2~\text V\) 2. \(44.4~\text V\)
3. \(4.4\times10^5~\text V\) 4. \(4\times10^4~\text V\)
Subtopic:  Electric Potential |
 78%
Level 2: 60%+
NEET - 2024
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Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): The potential \((V)\) at any axial point, at \(2~\text m\)  distance (\(r\)) from the centre of the dipole of dipole moment vector \(\vec P\) of magnitude, \(4\times10^{-6}~\text{C m},\) is \(\pm9\times10^3~\text{V}.\) (Take \({\dfrac{1}{4\pi\varepsilon_0}}=9\times10^9\) SI units)
Reason (R): \(V=\pm{\dfrac{2P}{4\pi\varepsilon_0r^2}},\) where \(r\) is the distance of any axial point situated at \(2~\text m\) from the centre of the dipole.
In the light of the above statements, choose the correct answer from the options given below:
1. Both (A) and (R) are True and (R) is not the correct explanation of (A).
2. (A) is True but (R) is False.
3. (A) is False but (R) is True.
4. Both (A) and (R) are True and (R) is the correct explanation of (A).
Subtopic:  Electric Potential |
 56%
Level 3: 35%-60%
NEET - 2024
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A thin spherical shell is charged by some source. The potential difference between the two points \(C\) and \(P\) (in V) shown in the figure is: 
( Take \(\dfrac{1}{4 \pi \epsilon_0}=9 \times 10^9\) SI units)
1. \(1 \times 10^5\) 2. \(0.5 \times 10^5\)
3. \(\text{zero}\) 4. \(3 \times 10^5\)
Subtopic:  Electric Potential |
 67%
Level 2: 60%+
NEET - 2024
Hints

If a conducting sphere of radius \(R\) is charged. Then the electric field at a distance \(r(r>R)\) from the centre of the sphere would be, (\(V=\) potential on the surface of the sphere):
1. \(\dfrac{rV}{R^2}\) 2. \(\dfrac{R^2V}{r^3}\)
3. \(\dfrac{RV}{r^2}\) 4. \(\dfrac{V}{r}\)
Subtopic:  Electric Potential |
 50%
Level 3: 35%-60%
NEET - 2023
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An electric dipole is placed as shown in the figure.

The electric potential (in \(10^2~\text{V}\)) at the point \(P\) due to the dipole is:
(\(\varepsilon_0=\) permittivity of free space and \(\dfrac{1}{4 \pi \varepsilon_0}=k\))
1. \(\left(\dfrac{8}{3}\right)qk\) 2. \(\left(\dfrac{3}{8}\right)qk \)
3. \(\left(\dfrac{5}{8}\right)qk\) 4. \(\left(\dfrac{8}{5}\right)qk\)
Subtopic:  Energy of Dipole in an External Field |
 65%
Level 2: 60%+
NEET - 2023
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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. \(\dfrac{1}{4\pi \varepsilon_0}\dfrac{Q}{R}\)
Subtopic:  Electric Potential |
 65%
Level 2: 60%+
NEET - 2022
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Two hollow conducting spheres of radii \(R_1\) and \(R_2\) \(\left ( R_1\gg R_2 \right )\) are concentric and have equal charges. The potential would be:
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
Subtopic:  Electric Potential |
 70%
Level 2: 60%+
PMT - 2022
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Two charged spherical conductors of radii \(R_1\) and \(R_2\) are connected by a wire. The ratio of surface charge densities of spheres \(\left ( \dfrac{\sigma _{1}}{\sigma _{2}}\right ) \) is:
1. \(\sqrt{\dfrac{R_1}{R_2}}\) 2. \(\dfrac{R^2_1}{R^2_2}\)
3. \(\dfrac{R_1}{R_2}\) 4. \(\dfrac{R_2}{R_1}\)
Subtopic:  Electric Potential |
 69%
Level 2: 60%+
NEET - 2021
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