Physics 9702 · AS & A Level · Electric force between point charges
Electric force between point charges — practice question
A helium nucleus has two protons. In a simplified model of the helium nucleus, each proton is treated as a charged point mass. The gap between these point masses is assumed to be $2.0 \times 10^{-15}\,\text{m}$.
(a(i))[2]
Calculate the electrostatic force for the two protons in this model.
(a(ii))[2]
Calculate the gravitational force for the two protons in this model.
(b(i))[3]
Using your answers in (a), suggest why there must be some other force between the protons in the nucleus.
(b(ii))[2]
Using your answers in (a), suggest why this additional force must have a short range.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Applies $F_E = \dfrac{Q_1Q_2}{4\pi\varepsilon_0 r^2}$” …