Physics Unit Review. 3. The electric field between a positive point charge and a negative point charge is represented by

Transcription

1 Physics Unit Review 1. What is the gravitational field strength on the surface of a planetoid with a mass of 7.4 x kg and a radius of 1.7 x 10 6 m? a N/kg b N/kg c. 9.8 N/kg d. 2.9 x 10 6 N/kg 2. An alpha particle is a sub-atomic particle with a charge of x C. The intensity and direction of the electric field produced by an alpha particle at a distance of 5.0 x m from the particle is a. 5.8 x N/C, toward the alpha particle b. 5.8 x N/C, away from the alpha particle c. 1.2 x N/C, toward the alpha particle d. 1.2 x N/C, away from the alpha particle 3. The electric field between a positive point charge and a negative point charge is represented by 4. An automobile s battery delivers a steady DC current to a headlight. The electric current in the wire produces a circular a. electric field around the wire b. magnetic field around the wire c. gravitational field around the wire d. electromagnetic field around the wire

2 5. Which of the following diagrams illustrates the magnetic field surrounding a bar magnet? Use the following information to answer the next question. A bar magnet is free to rotate while in a magnetic field. It is initially positioned as shown. The arrows indicate the direction of the magnetic field. 6. Which diagram shows the final orientation of the bar magnet?

3 7. Given the magnetic fields illustrated above, the magnets will repel in diagrams a. I and II only b. II and III only c. I and IV only d. II and IV only 8. Electricity is transmitted at high potential to a. operate heavy equipment. b. maximize current in the transmission lines. c. minimize the energy lost as heat in the transmission lines. d. produce alternating currents because they always require high voltages.

4 9. A 6.0-ohm lamp requires 0.25 ampere of current to operate. In which circuit below would the lamp operate correctly when switch S is closed? a. b. c. d. 10. A high-intensity halogen desk lamp operates at 1.25 A and 12.0 V AC. It has a built-in transformer to step down the 110 V AC obtained from the wall outlet. If the transformer is ideal, the current used from the wall outlet when the lamp is switched on is a A b A c A d A 11. What current would be drawn from the power supply in the circuit shown below? a A b A c A d A

5 12. Which of the following statements best describes the diagram above? a. Circuit Y dissipates more power than does circuit X. b. The current in circuit Y is larger than the current in circuit X. c. The current in circuit Y is the same as the current in circuit X. d. The current in circuit Y is smaller than the current in circuit X. 13. During its operation, the microwave oven draws a current of a A b A c A d A 14. The wavelength of the microwave radiation produced by the oven, expressed in scientific notation, is a.bc x 10 d m. The values of a, b, c, and d are,,, and.

6 15. In which circuit represented below are meters properly connected to measure the current through resistor R 1 and the voltage across resistor R 2? a. b. c. d.

7 16. The diagram below represents straight wave fronts passing from deep water into shallow water, with a change in speed and direction. Which phenomenon is illustrated in the diagram? a. reflection b. diffraction c. refraction d. polarization 17. Electromagnetic radiation having a wavelength of meter would be classified as a. infrared b. blue c. orange d. ultraviolet 18. When white light passes through a cool gas and then into a spectroscope, the spectrum produced is a. a continuous spectrum b. an absorption spectrum c. a bright-line spectrum d. an emission spectrum

8 Use the following information to answer the next question. 19. Given the information above, the element that emits the lowest energy waves of visible light is a. strontium b. barium c. copper d. sodium 20. When comparing a normal spectrum of iron with a spectrum of iron from an unidentified object in space, scientists found that the unidentified object exhibited a. red shift, which indicated that the object was moving toward the space station b. blue shift, which indicated that the object was moving toward the space station c. red shift, which indicated that the object was moving away from the space station d. blue shift, which indicated that the object was moving away from the space station