app In the figure below, a steel bar sitting on two parallel metal rails, connected to each other by a resistor, is pulled to the right with a constant force of magnitude F = 1.45 N. The friction between the bar and rails is negligible. The resistance R 8.00, the bar is moving at a constant speed of 1.55 m/s, the distance between the rails is {, and a uniform magnetic field B is directed into the page. = w R F Fapp (a) What is the current through the resistor (in A)? A (b) If the magnitude of the magnetic field is 3.00 T, what is the length l (in m)? 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 3.00 T at time t = O and increases at a constant rate of 0.500 T/s. The bar starts at an initial position Xo = 0.100 m to the right of the resistor at t = 0, and again moves at a constant speed of 1.55 m/s. Derive time-varying expressions for the following quantities. (e) the current through the 8.00 Q 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) = = A (f) the magnitude of the applied force F units in your answer.) required to keep the bar moving at a constant speed (Use the following as necessary: t. Assume F app (t) is in N and t is in s. Do not include app Fa (t) = N app

app In the figure below, a steel bar sitting on two parallel metal rails, connected to each other by a resistor, is pulled to the right with a constant force of magnitude F = 1.45 N. The friction between the bar and rails is negligible. The resistance R 8.00, the bar is moving at a constant speed of 1.55 m/s, the distance between the rails is {, and a uniform magnetic field B is directed into the page. = w R F Fapp (a) What is the current through the resistor (in A)? A (b) If the magnitude of the magnetic field is 3.00 T, what is the length l (in m)? 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 3.00 T at time t = O and increases at a constant rate of 0.500 T/s. The bar starts at an initial position Xo = 0.100 m to the right of the resistor at t = 0, and again moves at a constant speed of 1.55 m/s. Derive time-varying expressions for the following quantities. (e) the current through the 8.00 Q 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) = = A (f) the magnitude of the applied force F units in your answer.) required to keep the bar moving at a constant speed (Use the following as necessary: t. Assume F app (t) is in N and t is in s. Do not include app Fa (t) = N app