a) Two resistors in series with the Multiple Choice Answers This reduces the currents to the required 0.5 A. B b) 24 Ω B c) 6 W B D a) 288 Ω D b) 50 W A c) The power is less. B d) 0.42 A C e) 80 V B f) 40 V C C a) 24 Ω D b) 0.6 V A c) 0.15 A C d) 6 V C e) 1.5 W A B a) 8 Ω C b) 1.3 A B c) 10.7 V D d) 2.25 W D e) 1.7 W C B a) The 40W bulb does have a lower D resistance than the 30W bulb so D when the voltage across each is the A same, the lower the resistance the B higher the power. However the C voltage is only the same for each A, D bulb when they are connected in B, D parallel. B, C b) The 30W bulb does have a A, D higher resistance than the 40W bulb so when the current though each Free Response Answers light bulb is the same the higher the resistance, the higher the power. a) Heating coils in parallel, voltmeter However, they will only have the in parallel, ammeter in series. same current when they are b) 1.3 A connected in series. c) 11.35 V c) Ranking: 2, 1, 3, 4 d) 14.9 W Corresponding powers: 40W, 30W, e) 4470 J 9.4W, 7.1W
Multiple Choice Answers B B B D D A B C B C C D A C C A B C B D D C B D D A B C A, D B, D B, C A, D Free Response Answers a) Heating coils in parallel, voltmeter in parallel, ammeter in series. b) 1.3 A c) 11.35 V d) 14.9 W e) 4470 J a) Two resistors in series with the This reduces the currents to the required 0.5 A. b) 24 Ω c) 6 W a) 288 Ω b) 50 W c) The power is less. d) 0.42 A e) 80 V f) 40 V a) 24 Ω b) 0.6 V c) 0.15 A d) 6 V e) 1.5 W a) 8 Ω b) 1.3 A c) 10.7 V d) 2.25 W e) 1.7 W a) The 40W bulb does have a lower resistance than the 30W bulb so when the voltage across each is the same, the lower the resistance the higher the power. However the voltage is only the same for each bulb when they are connected in parallel. b) The 30W bulb does have a higher resistance than the 40W bulb so when the current though each light bulb is the same the higher the resistance, the higher the power. However, they will only have the same current when they are connected in series. c) Ranking: 2, 1, 3, 4 Corresponding powers: 40W, 30W, 9.4W, 7.1W
ap_physics_i-electric_circuit_mc_problems.docx