State what electric field strength means.
Charges A and B are two point charges separated by $15\,\text{cm}$ in a vacuum, as shown in Fig. 5.1. Point P is on the line joining the charges and lies a distance $x$ from charge A. Fig. 5.2 shows how the electric field strength $E$ at point P changes with distance $x$.
By referring to the direction of the electric field, state and explain whether charges A and B have the same sign or opposite signs.
State why, even though charge A is a point charge, the electric field strength between $x = 3\,\text{cm}$ and $x = 7\,\text{cm}$ does not follow an inverse-square law.
Use Fig. 5.2 to find the ratio \( \dfrac{\text{magnitude of charge A}}{\text{magnitude of charge B}} \).
Using the direction of the electric field, state and explain whether charges A and B carry like signs or unlike signs.
State why, even though charge A is a point charge, the electric field strength between $x = 3\,\text{cm}$ and $x = 7\,\text{cm}$ does not follow an inverse-square law.
Use Fig. 5.2 to determine the ratio $\dfrac{\text{magnitude of charge A}}{\text{magnitude of charge B}}$.