DP Physics (last assessment 2024)

Question 21N.2.HL.TZ0.b.ii

b.ii.

[Maximum mark: 3]

21N.2.HL.TZ0.b.ii

A conducting sphere has radius 48 cm. The electric potential on the surface of the sphere is 3.4 × 10⁵ V.

The sphere is connected by a long conducting wire to a second conducting sphere of radius 24 cm. The second sphere is initially uncharged.

Predict the charge on each sphere.

[3]

Markscheme

$k \frac{q_{1}}{48} = k \frac{q_{2}}{24} \Rightarrow q_{1} = 2 q_{2}$ ✓

$q_{1} + q_{2} = 18$ ✓

so $q_{1} = 12$ «μC», $q_{2} = 6.0$ «μC» ✓

Award [3] marks for a bald correct answer.

Syllabus sections