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In the figure below, a metal bar sitting on two parallel conducting rails, connected to each other by a resistor, is pulled to the right with a constant force of magnitude Fapp=1.30 N. The friction between the bar and rails is negligible. The resistance R = 8.000, the bar is moving at a constant speed of 2.15 m/s, the distance between the rails is f, and a uniform magnetic field B is directed into the page. (a) What is the current through the resistor (in A)? (b) If the magnitude of the magnetic field is 2.90 T, what is the length ( (in m)? (c) What is the rate at which energy is delivered to the resistor (in W)? W (d) What is the mechanical power delivered by the applied constant force (in W)? W What If? Suppose the magnetic field has an initial value of 2.90 T at time t = 0 and increases at a constant rate of 0.500 T/s. The bar starts at an initial position x = 0.100 m to the right of the resistor at t = 0, and again moves at a constant speed of 2.15 m/s. Derive time-varying expressions for the following quantities. (e) the current through the 8.000 resistor R (Use the following as necessary: t. Assume I(t) is in A and t is in s. Do not include units in your answer.) I(t) = (f) the magnitude of the applied force Fapp required to keep the bar moving at a constant speed (Use the following as necessary: t. Assume Fapp(t) is in N and t is in s. Do not include units in your answer.) Fapp(t)= N