20.2b Ex2 FM19 P42 Q8 Change in Balance Reading | A2 Magnetic Fields Cambridge A Level Physics

Example 2 - 9702/42/F/M/19: A horseshoe magnet is placed on a top pan balance. A rigid copper wire is fixed between the poles of the magnet, as illustrated in Fig. 8.1. The wire is clamped at ends A and B. (a) When a direct current is switched on in the wire, the reading on the balance is seen to decrease. State and explain the direction of: (i) the force acting on the wire (ii) the current in the wire. (b) A direct current of 4.6 A in the wire causes the reading on the balance to change by 4.5 × 10 –3 N. The direct current is now replaced by an alternating current of frequency 40 Hz and root-mean-square (r.m.s.) value 4.6 A. On the axes of Fig. 8.2, sketch a graph to show the change in balance reading over a time of 50 ms. #9702m19p42 #A2currentBalanceP4 #Lv3 #A2MagneticFields Playlist:    • Ch20 Magnetic Fields (Part 1) | CAIE 9702 ...   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_m19_qp42 #CambridgeALevelPhysics