Q21: Force acting on a conducting bar in magnetic field
The figure above is a metal bar that is supported by two sections of a fixed, conducting U-shaped horizontal rail. The rod and rail relocated in a region of magnetic field `B` directed into the page. The bar is moving to the right at a constant speed. Which of the following is true of the horizontal force acting on the bar? When the bar move to the right, the area of the loop is increasing, and the flux inside the loop is increasing too. Thus, there is a current in the loop flows counterclockwise. The current in the bar is going upward, user right hand rule, you can find the a magnetic force to the left.