Final answer:
A square bar sliding down inclined conducting rails in the presence of a magnetic field acquires a terminal velocity given by the equation v = B² 1² cos²0. The power dissipated in the Joule heating of the bar can be calculated. Reversing the magnetic field will change the direction of the force on the bar.
Step-by-step explanation:
In the given scenario, a square bar is sliding without friction down inclined conducting rails in the presence of a vertical magnetic field. The bar acquires a terminal velocity given by the equation v = B² 1² cos²0, where B is the magnetic field strength and 0 is the angle of inclination of the rails.
The power dissipated in the Joule heating of the bar can be calculated by multiplying the current flowing through the bar with the resistance of the bar.
If the magnetic field B is reversed, the direction of the induced current will also reverse, resulting in a change in the direction of the force acting on the bar.