Available practice: 75 of 80 marks. Parts 3(b), 6(a)(i) await marking support. Scores cover available parts only.
As the ball oscillates, it touches each plate in turn.
(a)Referring to the charge on the ball, explain why the ball moves to the positive plate after touching the negative plate.
Answer guidance
Using You must use the thing it names. An answer that reaches the right value another way may not score.
[2 marks]
(b)State which particles move when there is a current and state the direction in which they move through the sensitive ammeter.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[2 marks]
A conducting ball oscillates between two charged plates connected to a sensitive ammeter. For each complete oscillation of the ball moving between the plates, a charge of 8.5 × 10⁻¹⁰ C is transferred from one plate to the other. The frequency of oscillation is 4.0 Hz.
(c)Calculate the current shown on the sensitive ammeter.
Answer guidance
Calculate Show your working. The method can earn marks even when the final value is wrong, and a bare answer often cannot.
