State what the term electric field means.
A particle with mass $m$ and charge $q$ is placed in a uniform electric field of strength $E$. The field causes it to accelerate at $a$. Show that $a = \frac{Eq}{m}$.
A nucleus $X$ at rest emits an $\alpha$-particle and changes into a plutonium nucleus, $^{240}_{94}\text{Pu}$, as shown: $X \rightarrow {}^{240}_{94}\text{Pu} + \alpha$. Determine the number of protons and the number of neutrons in nucleus $X$.
The combined mass of the plutonium nucleus and the $\alpha$-particle is less than the mass of nucleus $X$. Explain why this mass difference occurs.
The plutonium nucleus and the $\alpha$-particle are both accelerated by the same uniform electric field. Use the expression in (b) to determine the ratio $\dfrac{\text{acceleration of the } \alpha\text{-particle}}{\text{acceleration of the plutonium nucleus}}$.
The plutonium nucleus and the $\alpha$-particle are both accelerated by the same uniform electric field. Use the expression in (b) to work out the ratio $$\frac{\text{acceleration of the }\alpha\text{-particle}}{\text{acceleration of the plutonium nucleus}}$$.