Two charges M and N are separated by a certain distance, as shown in the diagram.

Graphs I, II, and III show the variation of electric potential $V_e$ With distance x from the centre of charge M.

Which of the possibilities below applies o the case of two equal and opposite charges?

A sphere of radius $0.25 \mathrm{m}$ has positive charge $+8.8 \mathrm{\mu C}$ uniformly distributed on its surface. A small pellet of mass $0.075 \mathrm{kg}$ and charge $+2.4 \mathrm{\mu C}$ is directed radially at the sphere. When the pellet is at a distance of 0.75 m from the centre of the sphere its speed is $3.2 \mathrm{m} {\mathrm{s}}^{-1}$.

$\mathrm{a}.$ Determine the distance from the centre of the sphere at which the pellet will stop.

A sphere of radius $0.25 \mathrm{m}$ has positive charge $+8.8 \mathrm{\mu C}$ uniformly distributed on its surface. A small pellet of mass $0.075 \mathrm{kg}$ and charge $+2.4 \mathrm{\mu C}$ is directed radially at the sphere. When the pellet is at a distance of $0.75 \mathrm{m}$ from the centre of the sphere its speed is $3.2 \mathrm{m} {\mathrm{s}}^{-1}$.

$\mathrm{b}.$ Describe qualitatively the subsequent motion of the pellet.

A sphere of radius $0.25 \mathrm{m}$ has positive charge $+8.8 \mathrm{\mu C}$ uniformly distributed on its surface. A small pellet of mass $0.075 \mathrm{kg}$ and charge $+2.4 \mathrm{\mu C}$ is directed radially at the sphere. When the pellet is at a distance of $0.75 \mathrm{m}$ from the centre of the sphere its speed is $3.2 \mathrm{m} {\mathrm{s}}^{-1}$.

$\mathrm{c}.$ Determine the speed of the pellet after it moves very far from the sphere.