Q4.20Very short answer
Do magnetic forces obey Newton’s third law. Verify for two current elements dl1 = dl î located at the origin and dl2 = dl ĵ located at (0, R, 0). Both carry current I. R1 R2 R3 G 4.21 A multirange voltmeter can be constructed by using a galvanometer circuit as shown in Fig. 4.2. We want to construct a voltmeter that can measure 2V, 20V and 200V using a galvanometer of resistance 10Ω and that produces maximum deflection for current of 1 mA. Find R1, R 2 and R3 that have to be used. 2V 20V 200V Fig. 4.2
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