Define electric potential at a point in a field.
State how the magnitude of the electric field strength at any point P can be found from the graph of Fig. 5.2.
Without doing any calculations, describe the force on a positively charged particle at point P for $x$ ranging from $x = 0$ to $x = 10\,\text{cm}$.
On Fig. 5.2, place the letter M at the point where the charged particle has its maximum speed.
Use Fig. 5.2 to find the potential difference between the spheres.
Use your result from (ii) part 1 to work out the speed of the particle as it reaches the surface of sphere B. Show your working.
In (b)(ii), the positively charged particle has charge $q$ and mass $m$, with $\frac{q}{m} = 4.8 \times 10^{7}\,\text{C kg}^{-1}$. Initially, it is at rest on the surface of sphere A at $x = 0$. It then moves freely along the line joining the centres of the spheres until it reaches the surface of sphere B.
Use Fig. 5.2 to find the potential difference between the spheres.
Use your answer in (ii) part 1 to calculate the speed of the particle as it reaches the surface of sphere B. Explain your working.