10.3b Ex4 MJ12 P21 Q5 Terminal pd Potentiometer | AS DC Circuits | Cambridge A Level 9702 Physics

Example 4 - 9702/21/M/J/12: (a) (i) State Kirchhoff’s second law. (ii) Kirchhoff’s second law is linked to the conservation of a certain quantity. State this quantity. #9702s12p12 #ASpotentiometerP2 #Lv2 (b) The circuit shown in Fig. 5.1 is used to compare potential differences. The uniform resistance wire XY has length 1.00 m and resistance 4.0 Ω. Cell A has e.m.f. 2.0 V and internal resistance 0.50 Ω. The current through cell A is I. Cell B has e.m.f. E and internal resistance r. The current through cell B is made zero when the movable connection J is adjusted so that the length of XJ is 0.90 m. The variable resistor R has resistance 2.5 Ω. (i) Apply Kirchhoff’s second law to the circuit CXYDC to determine the current I. (ii) Calculate the potential difference across the length of wire XJ. (iii) Use your answer in (ii) to state the value of E. (iv) State why the value of the internal resistance of cell B is not required for the determination of E. #DCcircuits Chapter Playlist:    • Ch10 DC Circuits | CAIE 9702 AS Physics   Instagram Pocket Guide (  / etphysics  ) More Resources (https://9702-physics.blogspot.com/) Support us! (  / etphysics  ) Tuition/Tutoring inquiries: Email: [email protected] Whatsapp: https://wa.me/60126679171 Recorded at MCKL #CambridgeALevelPhysics 9702_s12_qp21