A light, polystyrene ball is coated with a thin layer of metal - Edexcel - GCSE Physics - Question 2 - 2012 - Paper 1
Question 2
A light, polystyrene ball is coated with a thin layer of metal.
Diagram 1 shows the ball on a metal plate.
In diagram 2, the plate has been charged and the ball is r... show full transcript
Worked Solution & Example Answer:A light, polystyrene ball is coated with a thin layer of metal - Edexcel - GCSE Physics - Question 2 - 2012 - Paper 1
Step 1
State the sign of the charge on the ball as it moves upwards.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The charge on the ball as it moves upwards is positive. This is inferred from the setup, as the ball is influenced by the positively charged plate.
Step 2
Explain why the ball moves upwards.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The ball moves upwards due to the repulsion between the charges on the ball and the plate. As both the ball and the plate are positively charged, they repel each other, causing the ball to rise.
Step 3
Explain how the ball loses its charge.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The ball discharges when it contacts the earthed lid. During this contact, electrons from the lid move into the ball, neutralizing its positive charge.
