What is the direction of the acceleration due to gravity for an object on the surface of Earth? a. It does not vary with location on Earth. b. It is toward the centre of Earth. c. It is always tangent to the surface of Earth. (1. It is away from the centre of Earth. Which of the following is the correct equation for the speed of a satellite in orbit around Earth? a. 6:132 v = r b. GmE _ r: C. GmE v = r (1. 6mm 1) = r: What is space junk? a. It is debris from articial objects orbiting Earth. b. It refers specically to discarded rocket boosters that did not return to Earth. c. It consists both of wanted objects such as GPS satellites and unwanted objects such as discarded rocket boosters. d. It refers to satellites that will never return to Earth. Which statement correctly describes the density of electric eld lines? The density increases with separation from a point charge. The density is proportional to the magnitude of the electric force. The density decreases with distance from a point charge. The density decreases when approaching a negative point charge. 999'?\" 5. Which statement describes the behaviour of a charged particle in an electric field? a. It remains at rest. b. It always accelerates in the direction of the field. c. It accelerates in the direction of the field if it is positively charged. d. It does work on the electric field as it accelerates. 6. A fixed negative charge Q creates an electric field. A positive test charge q is located a distance r from the field. The test charge is allowed to move freely. Which of the following statements is true? a. The electrical potential energy of q increases as it moves. b. The electrical potential energy of q decreases and the kinetic energy of q increases. c. The electrical potential energy of q increases and the kinetic energy of q decreases. d. The charge q does work on the field as it moves.10. Which equation gives the electric potential due to a charge q at a distance r? . k a V= _gr r b kg V= r2 c 2 V- *1 r d kg: V= r: The electric potential due to a unit charge g at a distance r is V. What is the potential due to a charge of 4:; at a distance of 2r? a. 2V b. V c. l 5 V d. l 3 V What, by convention, is the reference point for the electric potential created by a point charge? a. zero potential at an innite distance from the charge b. zero potential at a unit distance from the charge c. zero potential at any convenient distance from the charge d. any of these can be used Point charge :11 creates a potential V1 at point P, and point charge :1, creates a potential V2 at point P. Which is true about the total electric potential at point P? a. equals V2 V1 b. equals V1 - V; c. equals V1 + V; d. cannot be determined without knowing the relative locations of the charges and the point P 11. What is the SI unit for the strength of a magnetic field? a. tesla b. coulomb c. newton d. joule12. A electric charge moves through an electric field from point P to point Q in a straight line through a distance, d. The field does 24.0 J of work on the charge. Suppose that the charge moved along a different path from A to B through a distance of 2d. What is the work done in this case? a. OJ b. 12.0 J C. 24.0 J d. 48.0 J 13. What is electric potential? a. the kinetic energy per unit charge b. the electric field strength per unit charge c. the work done per unit charge by an electric field d. the electric potential energy per unit charge 14. An electron is over the equator 100 m above the surface of Earth. It is at rest with respect to the magnetic field lines of Earth. What is true about the force on the electron due to the magnetic field of Earth? a. The force points to the east. b. The force points toward the west. c. The force points upward from the surface of Earth. d. The force equals O N. 15. Under what circumstances will the magnetic force acting on a proton in a magnetic field equal zero? a. The field is parallel to the motion of the proton. b. The proton is at rest with respect to the field. c. The angle between the field lines and the motion of the proton is 180. d. All of these