21.1c FM20 P42 Q9 Transformer AC Graphs | A2 Alternating Current | Cambridge A Level Physics

Example 2 - 9702/42/F/M/20: The output of a power supply is represented by V = 9.0sin20t where V is the potential difference in volts and t is the time in seconds. #9702m20p42 #A2transformersP4 #Lv2 Determine, for the output of the supply: (i) the root-mean-square (r.m.s.) voltage, Vr.m.s. (ii) the period T. (b) The variations with time t of the output potential difference V from two different power supplies are shown in Fig. 9.1 and Fig. 9.2. The graphs are drawn to the same scale. State and explain whether the same power would be dissipated in a 1.0Ω resistor connected to each power supply. (c) (i) The power supply in (a) is connected to a transformer. The input power to the transformer is 80W. The secondary coil is connected to a resistor. The r.m.s. voltage across the resistor is 120V. The r.m.s. current in the secondary coil is 0.64A. Calculate the efficiency of the transformer. (ii) State one reason why the transformer is not 100% efficient. #A2alternatingCurrent Playlist:    • Ch21 AC Circuits | CAIE 9702 A2 Physics   FM20 Paper Discussion Playlist:    • 9702 FM20 Papers CAIE 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 9702_m20_qp42 #CambridgeALevelPhysics