Within the nucleus, a proton decays to make a neutron and a $\beta^+$ particle. State the name of the other lepton that is created in the decay.
State the name of the interaction (force) responsible for producing this decay.
State which one of the three particles (proton, neutron or $\beta^+$ particle) has the greatest charge-to-mass ratio.
Use the quark model to demonstrate that the proton has charge $+e$, where $e$ represents the elementary charge.
The quark composition of the proton changes during the decay. Describe the change in the quark composition.
A nucleus $X$ ($^{12}_{6}X$) and a nucleus $Y$ ($^{16}_{8}Y$) are both accelerated by the same uniform electric field. Determine the ratio $$\frac{\text{electric force acting on nucleus } X}{\text{electric force acting on nucleus } Y}.$$
Determine the ratio $$\frac{\text{acceleration of nucleus } X \text{ due to the field}}{\text{acceleration of nucleus } Y \text{ due to the field}}.$$
Nucleus $X$ is initially at rest in the uniform electric field at time $t = 0$. The field makes nucleus $X$ accelerate as it travels through the field. On Fig. 6.1, sketch how the acceleration $a$ of nucleus $X$ due to the field varies with time $t$.