Consider a concave mirror with a focal length is 2cm. An object is placed facing the reective surface of the mirror, at a distance from the mirror that is shorter than its focal length. An image is formed at a distance of 4cm from the mirror. Determine the distance of the object from the mirror. A. 4.0 cm B 2.5 cm C. 1.33 cm D. 0.75 cm E 0.25 cm The gure below shows 3 circuits with ideal and identical batteries, identical resistors, and wires. Magnetic eld detectors are placed at the points labeled i, ii, and iii, all the same (very small!) distance from the nearby wire. The detector measure the strength of the magnetic elds created by the wires immediately to their right. You may ignore any magnetic elds created by the more distant wires. Rank the magnitudes of the magnetic elds at those three points, from largest to smallest. Bi > Biii > Ba\" Bi = Biii = Biz' Bi = Biii > Bit Bi. = Bii > 311:? Biii > Bi > B $11.00.\"? In the gure below, suppose B=1.0 T, d = 0.1 m, and the rod is initially a distance h = 5.0 m from the end of the track, as shown. The rod has resistance 4.0 Ohm, and the rest of the track may be considered resistanceless. The rod travels downward at a constant velocity v for 0.1 seconds. If the induced current in the rod is 1.0 A during this time period, what was the velocity v of the rod? A. 40 m/s (9 B. 1.0 m/s 3 C. 10 m/s D. 0.025 m/s An electromagnetic wave (not pictured!) is traveling from point A to point B in the diagram below. Between these two points, a proton is oating alone in space. At a particular instant in time, the proton is feeling an upward electric force due to the passing electromagnetic wave. What is the direction of the magnetic field at the proton's location at this moment in time? A' 6') B' A. To the left