(a)[1]
State the definition of electric field strength.
(b(i))[2]
A proton starts from rest on the positive plate. In the uniform electric field it takes $1.5 \times 10^{-7}\,\text{s}$ to arrive at the negative plate. Show that the proton’s acceleration is $4.0 \times 10^{12}\,\text{m s}^{-2}$.
(b(ii))[1]
Calculate the electric force acting on the proton.
(b(iii).1)[2]
Use your result from (ii) to find the electric field strength.
(b(iii).2)[2]
Use your result from (ii) to find the potential difference $V$ across the plates.
(c)[2]
An $\alpha$ particle is now accelerated by the electric field between the two metal plates in (b). Calculate the ratio $\dfrac{\text{acceleration of } \alpha \text{ particle}}{\text{acceleration of proton}}$.