Answers

. Which of the following diagrams best represents the magnetic field in the region between the two permanent magnets? (A) (B) N S N S N N (C) (D) N S N S N N 7. A charge X is placed in an electric field and a second charge Y is placed in a magnetic field. If both charges are initially held at rest, which one of the following best describes the motion of the charges after they are released? Ignore gravitational effects. (A) Charge X accelerates (B) Charge Y accelerates (C) Both charge X and charge Y accelerate (D) Neither charge X nor charge Y accelerate 8. The diagram below shows a solenoid connected to a battery with an open switch and a compass placed next to each open end of the solenoid. The Earth's magnetic field causes the compasses to point up the page when he switch is open. When the switch is closed, in what direction will the compass point? Left compass Right compass LEFT-END RIGHT-END COMPASS COMPASS (A) East East (B ) East West West East animed ant (d (C) (D) West West 9. The diagram shows the current flowing in a circular coil located in a magnetic field B. The magnetic force on the coil will tend to cause the coil to X X X X X B (A) Expand X X X X X (B) Contract X (C) Move up the page X X X X (D) Move down the page X X X X X X X X 10. A long straight wire is carrying a 70.0 A current. What is the magnitude of the magnetic field due to this current at a point 0.15 m from the wire? (A) 8.8 x 10 - T (B) 9.3 x 10 - T (C) 5.9 x 10 4T (D) 6.2 x 10 4 T