(9%) Problem 8: A flat rectangular wire loop is positioned next to a long straight current-carrying wire. Both the loop and the wire are in the plane of the page, and the direction of the current is clearly indicated in the figure. 14% Part (a) Which image best indicates the direction of the magnetic field due to the current in the long straight wire at a point inside the loop? Correct! 14% Part (b) How does the magnitude of the magnetic field change as the perpendicular distance from the wire, r, increases? From Ampre's Law we know that the magnitude of the magnetic field decreases as an inverse proportion to the perpendicular distance, that is, B & 1/r. Correct! 14% Part (c) Due to an external force, the loop begins to move towards the top of the page. Which statement best describes the change in the magnitude of the magnetic flux, |B|, and the direction of any induced EMF, &, as the loop just begins to move? The magnitude of the magnetic flux, |B|, is constant, and there is no induced EMF around the loop. Correct! 14% Part (d) The magnitude of the electric current in the long straight wires increases steadily. Which statement best describes the change in the magnitude of the magnetic flux, |B|, and the direction of any induced EMF, ? The magnitude of the magnetic flux, |DB], increases, and the direction of the induced EMF, E, counterclockwise around the loop. Correct! A 14% Part (e) Due to an external force, the loop begins to move towards the right of the page. Which statement best describes the change in the magnitude of the magnetic flux, |B|, and the direction of any induced EMF, E, as the loop just begins to move? 14% Part (f) The magnitude of the electric current in the long straight wires decreases monotonically towards zero. Which statement best describes the change in the magnitude of the magnetic flux, |B|, and the direction of any induced EMF, &? The magnitude of the magnetic flux, |PB], decreases, and the direction of the induced EMF, E, is clockwise around the loop. Correct! A 14% Part (g) Due to an external force, the loop begins to move towards the bottom of the page. Which statement best describes the change in the magnitude of the magnetic flux, |B|, and the direction of any induced EMF, &, as the loop just begins to move? The magnitude of the magnetic flux, |B|, decreases, and the direction of the induced EMF, &, is clockwise around the loop. The magnitude of the magnetic flux, |B|, increases, and the direction of the induced EMF, &, is counterclockwise around the loop. The magnitude of the magnetic flux, |B], increases, and the direction of the induced EMF, E, is clockwise around the loop. The magnitude of the magnetic flux, |B|, is constant, and there is no induced EMF around the loop. The magnitude of the magnetic flux, |B|, decreases, and the direction of the induced EMF, &, is counterclockwise around the loop. The magnitude of the magnetic flux, ||, decreases, and there is no induced EMF around the loop. Grade Summary Deductions Potential 0% 100% Submissions Attempts remaining: 5 (20% per attempt) detailed view