When the distance L of the metal guide rail is fixed horizontally, the resistance is neglected. The left end of the guide rail is connected with a resistance R. the uniform magnetic field B is perpendicular to the plane of the guide rail downward. The conductor bar with mass m, resistance R and length L is vertically placed on the guide rail to keep good contact with the guide rail. The dynamic friction factor between the conductor bar AB and the guide rail is μ (1) The direction and magnitude of the induced current in the conductor bar AB; (2) the electric power of the resistance R; (3) the magnitude of the external force F

When the distance L of the metal guide rail is fixed horizontally, the resistance is neglected. The left end of the guide rail is connected with a resistance R. the uniform magnetic field B is perpendicular to the plane of the guide rail downward. The conductor bar with mass m, resistance R and length L is vertically placed on the guide rail to keep good contact with the guide rail. The dynamic friction factor between the conductor bar AB and the guide rail is μ (1) The direction and magnitude of the induced current in the conductor bar AB; (2) the electric power of the resistance R; (3) the magnitude of the external force F

(1) According to Ohm's law of closed circuit, the induced electromotive force is e = BLV, and the induced current is I = ER + R. the solution is I = BLVR + R. according to the right-hand rule, the direction of the induced current in the conductor bar AB is from B to A. (2) the power of resistance R is p = I2R, and P = b2l2v2r (R + R) 2 (3) the ampere force on the conductor bar is f a = bil, and the equilibrium condition is f = f a + μ mg The external force is: F = b2l2vr + R + μ mg a: (1) the direction of the induced current in the conductor bar AB from B to a is BLVR + R; (2) the electric power of the resistance R is b2l2v2r (R + R) 2; (3) the external force F is b2l2vr + R + μ mg

A conductor rod is placed on two smooth guide rails with power supply and resistance, and a uniform magnetic field perpendicular to the plane of the guide rail inward, which gives the rod a right speed
Q: what is the final state of the conductor bar? The answer is to move in a straight line at a constant speed. I don't quite understand

What is the final state of the conductor bar? The answer is to move in a straight line at a constant speed
The meaning of the question is not very clear
If a conductor rod is placed on two smooth guide rails and does not form a current loop, the rod will only be balanced by gravity and move in a uniform straight line
If a current loop is formed, it is not necessary to give a right speed, and it will move automatically under the action of Ampere force. Then the electromotive force is generated by cutting the magnetic induction line. When the electromotive force generated by the conductor rod is equal to the electromotive force of the power supply, the current disappears and moves in a uniform straight line