Question

Question 4 a) Two 8k resistors are connected as a potential divider with a supply p.d. of 20 mv. What is the current flowing and the p.d. across each resistor? (5 mark) b) The circuit shows four arrangements A, to D of three 2uF capacitors which arrangement has the smallest capacitance, the largest capacitance. (5 mark) Total 10 marks Space to answer Question 4 here А B HHHE D HA

Answer 1

1.

2.

c= auf a a C₂ C3 HII- It tes + Effective capantes ca. ca -li CI ca + I ㅗ 2 x 10 4 I a X10 axiob 3 2x16b > Ca=6.6 7 x 10 107, b gien by C2 II Effectie capaclica & cb is cb = at catc3 20 + QuF + auf cb . 6 MF C2 j 벱 are Here series thed gien by a and ca is the effective capacticare +1 c3 Y cz 2 2 + L 2uP auf 2 MF CAT xioba This Ceff and C3 are parallel e3 1 x 10 Cca Ceff + Cc = + 2x100 = 3x156A 3 uf

C2 d. i 1 C3 Here ca are parallel, therefore the and effective copaeltance is cat + C3 Ceff 2uF+QUF = 4 MF. the ei. Iherefore This is in seris euith effectie Capacet tance J Itt ceff cd ci + I 2uF 4 MF ed 1. 33x106 F cd a 1.33 UF

webare Ca = 6.67 x 10 x 107 0.667 uF cb = 6 uf = I x 10-6F LUF. cc ed - 1.33 UF is Ca and the largest The smallest ose Cb - series seri ie, The capacitar connected in [CA) has the smallest capacitance and and the capaciter conneet poralul[(B) bare the largest Capacitance in

A - smallest capacitance

B - largest capacitance