Physics (AS & A Level) · Feb / March 2016 · Paper 22 · Question 5

movement / flow of charge carriers

work (done) or energy (transformed)(from electrical to other forms) charge

p.d. across one lamp = 2.5 V resistance = [(8.7 – 7.5) / 0.3] / 2 = 2.0 (Ω)

straight line through the origin with gradient of 0.5

P = I 2R or P = VI and V= IR or P = V 2 / R and V= IR = 0.302 × 2.0 = 0.60 × 0.30 = 0.602 / 2.0 = 0.18 (W)

1 R = ρl / A l = (2.0 × 0.40 × 10–6) / 1.7 × 10–8 = 47 (m) 2 I = Anvq v = 0.30 / (0.40 × 10–6 × 8.5 × 1028 × 1.6 × 10–19) = 5.5 × 10–5 (m s–1)