CP CALC Terminal Speed. A bar of length L = 0.36 m is free to slide without friction on horizontal rails as shown in Fig. P29.56. A uniform magnetic field B = 2.4 T is directed into the plane of the figure. At one end of the rails there is a battery with emf ε = 12 V and a switch S. The bar has mass 0.90 kg and resistance 5.0 Ω; ignore all other resistance in the circuit. The switch is closed at time t = 0. (a) Sketch the bar’s speed as a function of time. (b) Just after the switch is closed, what is the acceleration of the bar? (c) What is the acceleration of the bar when its speed is 2.0 m/s? (d) What is the bar’s terminal speed?
Figure P29.56
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