A bar of length $L =$ 0.36 m is free to slide without friction on horizontal rails as shown in $\textbf{Fig. P29.56}$. 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 $\varepsilon =$ 12 V and a switch S. The bar has mass 0.90 kg and resistance 5.0 $\Omega$; 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?