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 |
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NEET - 2022
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Work done in carrying a charge \(Q\) from \(A\) to \(B\) (as shown in the figure) on a circle of the radius \(r\) with a charge \(Q\) at the centre is:
1. \(\dfrac{1}{4 \pi \varepsilon_{0}} \dfrac{Q}{r}\) 2. \(\dfrac{Q^{2}}{4 \pi \varepsilon_{0} r}\)
3. zero 4. \(\dfrac{Q^{2}}{2 r}\)
Subtopic:  Electric Potential Energy |
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Three protons, each having a mass \(m\) and charge \(e,\) are placed at rest at the corners of an equilateral triangle with side length \(a.\) The electrostatic potential energy of the system is: \(\left (\text{here,}~ k=\dfrac{1}{4\pi \varepsilon _{0}} \right )\)
1. \(\dfrac{ke^{2}}{\varepsilon _{0}a}\) 2. \(\dfrac{3ke^{2}}{a}\)
3. \(\dfrac{3ke^{2}}{a^{2}}\) 4. \(\dfrac{ke^{2}}{a^{2}}\)
Subtopic:  Electric Potential Energy |
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If \(E\) is the electric field intensity of an electrostatic field, then the electrostatic energy density is proportional to:
1. \(E\) 2. \(E^2\)
3. \(\dfrac{1}{E^2}\) 4. \(E^3\)
Subtopic:  Electric Potential Energy |
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Two charges q1 and q2 are placed 30 cm apart, as shown in the figure. A third charge q3 is moved along the arc of a circle of radius 40 cm from C to D. The change in the potential energy of the system is q34π0k, where k is: 

            

1.  8q2
2.  6q2
3.  8q1
4.  6q1

Subtopic:  Electric Potential Energy |
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Two free charge particles of the same mass (\(m\)) and charge (\(q\)), separated by a distance \(r\), are released, when the charged particles reach at infinite separation, then the potential energy that is converted into kinetic energy will be: (consider at infinity potential is zero)
1. \(\dfrac{1}{2 \pi \varepsilon_{0}}\left(\dfrac{q^{2}}{r}\right)\)
2. \(\dfrac{1}{4 \pi \varepsilon_{0}}\left(\dfrac{q^{2}}{r}\right)\)
3. \(\dfrac{1}{4 \pi \varepsilon_{0}}\left(\dfrac{q^{2}}{r^2}\right)\)
4. \(\dfrac{1}{4 \pi \varepsilon_{0}}\left(\dfrac{2q^{}}{r}\right)\)
Subtopic:  Electric Potential Energy |
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A particle of mass \(0.002\) kg and charge \(1 ~\mu\text{C}\) is held at rest on a frictionless horizontal surface at a distance of \(1\) m from a fixed charge of \(1\) mC. If the particle is released, it will be repelled. The speed of the particle when it is at a distance of \(10\) m from the fixed charge will be:
1. \(60\) ms–1 2. \(75\) ms–1
3. \(90\) ms–1 4. \(100\) ms–1
Subtopic:  Electric Potential Energy |
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Twenty-seven identical spherical drops of mercury are each maintained at a potential of \(10~\text{V}.\) If all these drops coalesce to form a single large spherical drop, then the potential energy of this larger drop will be how many times that of one of the smaller drops?

1. \(143\) 2. \(243\)
3. \(348\) 4. \(564\)
Subtopic:  Electric Potential Energy |
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A charge \(Q=2~\mu \text{C}\) is situated at the origin of co-ordinate axis. Another charge \(5~\mu\text{C}\) on the \(x\text-\)axis at point \(A(3,0) \) is brought to point \(B(0,2) \) on \(y\text-\)axis. The work done by an external agent is: 

         
1. \(12~\text{mJ}\)
2. \(15~\text{mJ}\)
3. \(20~\text{mJ}\)
4. \(34~\text{mJ}\)
Subtopic:  Electric Potential Energy |
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