Physical Science Goal 3 Study Guide (Energy, Electricity, and Waves)

  1. Thermal Energy, Heat, and Temperature
  2. ______- the total kinetic energy of a substance’s atoms
  3. ______- a measure of how hot (or cold) something is; specifically, a measure of the average kinetic energy of the particles in an object.
  4. ______- the energy transferred between objects that are at different temperatures.
  5. Heat Transfer- Conduction, convection, and radiation
  6. ______- the transfer of energy by electromagnetic waves.
  7. ______- the transfer of energy between two objects that are in contact.
  8. ______- the movement of matter due to differences in density that era caused by temperature variations; can result in the transfer of energy as heat.
  9. At the top of a ramp a ball has 100 J of PE and 0 J of KE. As the ball rolls down the hill the potential energy is transformed into kinetic energy. If friction is ignored, how much kinetic energy does the ball have at the bottom of the ramp?
  10. At the top of a hill a rollercoaster has 1500 J of PE and 0 J of KE. At the bottom of the hill the rollercoaster is found to have 1250 J of KE and 0 J of PE. What happened to the “missing” energy?
  11. Work requires energy; when work is done on an object, the result is an ______in its energy and is accompanied by a ______in energy somewhere else.
  12. Is work being done is the following situations?
  13. A teacher applies a force to a wall and becomes exhausted. Explanation:
  14. A weightlifter lifts a barbell above her head. Explanation:
  15. A waiter carries a tray full of meals across a dining room at a constant speed. Explanation:
  16. A rolling marble hits a note card and moves it across a table. Explanation:
  17. A shot-putter launches the shot. Explanation:
  18. W = F * d (work = force x displacement)
  19. Force and displacement must be in the same ______.
  20. A car breaks down 2.1 m from the shoulder of the road. 1990 N of force is used to push the car off the road. How much work has been done on the car?
  21. Pulling a boat forward into a docking slip requires 1570 J of work. The boat must be pulled a total distance of 5.3 m. What is the force with which the boat is pulled?
  22. A mechanic uses a hydraulic lift to raise a 1200 kg car 0.5 m off the ground. How much work does the lift do on the car?
  23. P = W / t (Power = Work / Time)
  24. While rowing across the lake during a race, John does 3960 J of work on the oars in 60.0 s. What is his power output in watts?
  25. Using a jack, a mechanic does 5350 J of work to lift a car 0.500 m in 50.0s. What is the mechanic’s power output?
  26. Suppose you are moving a 300 N box of books. Calculate your power output in the following situations:
  27. You exert a force of 60.0 N to push the box across the floor 12.0 m in 20.0 s.
  28. You lift the box 1 m onto a truck in 3 s.
  29. Mechanical Advantage
  30. IMA = de / dr (Ideal Mechanical Advantage = effort distance / resistance distance)
  31. AMA = Fr / Fe (Actual Mechanical Advantage = resistance force / effort force)
  32. Calculate the mechanical advantage of a ramp that is 6.0 m long and 1.5 m high.
  33. Determine the mechanical advantage of an automobile jack that lifts a 9900 N car with an input force of 150 N.
  34. A sailor uses a rope and pulley to raise a sail weighing 140 N. The sailor pulls down with a force of 140 N on the rope. What is the mechanical advantage of the pulley?
  35. Alex pulls on the handle of a claw hammer with a force of 15 N. If the hammer has a mechanical advantage of 5.2, how much force is exerted on a nail in the claw?
  36. While rowing in a race, John pulls the handle of an oar 0.80 m on each stroke. If the oar has a mechanical advantage of 1.5, how far does the blade of the oar move through the water on each stroke?
  37. Efficiency = Wout / Win x 100% (Wout= work output; Win = work input)
  38. Alice and Jim calculate that they must do 1800 J of work to push a piano up a ramp. However, because they must also overcome friction, they actually must do 2400 J of work. What is the efficiency of the ramp?
  39. It takes 1200 J of work to lift the car high enough to change a tire. How much work must be done by the person operating the jack if the jack is 25 percent efficient?
  40. A windmill has an efficiency of 37.5 percent. If a gust of wind does 125 J of work on the blades of the windmill, how much output work can the windmill do as a result of the gust?
  41. Why can no machine be 100% efficient?
  42. Identify the basic characteristics of a longitudinal wave: amplitude, rarefaction, wavelength, and compression.
  43. Identify the basic characteristics of a transverse wave: crest, trough, amplitude, wavelength, and rest position.
  44. Compare longitudinal and transverse waves in terms of particle motion relative to wave direction.
  45. Describe the inverse relationship between period and frequency. If the period increases, then the frequency will ______.
  46. Vw = f x λ (wave velocity = frequency x wavelength)
  47. If the frequency of a wave is increased and the wavelength remains constant the wave velocity will ______. (direct)
  48. If the wavelength of a wave is increased and the frequency remains constant the wave velocity will ______. (direct)
  49. If the frequency of a waves is increased and the wave velocity remains constant the wavelength will ______. (inverse)
  50. The average wavelength in a series of ocean waves is 15.0 m. A wave crest arrives at the shore on average every 10.0s, so the frequency is 0.100 Hz. What is the average speed of the waves?
  51. An FM radio station broadcasts electromagnetic waves at a frequency of 94,500,000 Hz. These radio waves have a wavelength of 3.17 m. What is the speed of the waves?
  52. The speed of sound in air is about 340 m/s. What is the wavelength of a sound wave with a frequency of 220 Hz?
  53. Amplitude is directly related to the energy of a wave. The greater the energy carried by the wave the ______the amplitude.
  54. Electromagnetic wave or mechanical wave:

Type of wave / ______waves / ______waves
Type of material required / None required / Solid, liquid, or gas
Wave speed / Speed of light / Depends on the medium
Motion of the particles / Transverse / Transverse or longitudinal
  1. Reflection, Refraction, Diffraction, or Interference?
  2. ______- a change in the direction of a wave when the wave finds an obstacle or an edge, such as an opening.
  3. ______-the combination of two or more waves of the same frequency that results in a single wave.
  4. ______-the bouncing back of a ray of light, sound, or heat when the ray hits a surface that it does not go through.
  5. ______-the bending of a light ray as it passes from one substance to another one with a different density.
  6. Opposite charges ______and like charges ______.
  7. Charging by conduction, friction, or induction?
  8. ______-some electrons are transferred between your clothes and the car seat. One material gains electrons and becomes negatively charged, and the other loses electrons and becomes positively charged.
  9. ______-One way to charge an object is by touching it with a charged object. When the negatively charge rubber rod touches a neutral object, like a doorknob, some electrons move from the rod to the doorknob. The doorknob then has a net negative charge. The rubber rod still has a negative charge, but the charge is smaller.
  10. ______-A negatively charged rod brought near a metal doorknob induces a positive charge on the side of the doorknob closest to the rod and a negative charge on the side farthest from the rod.
  11. Explain open and closed circuits. Draw a picture of an open circuit and a closed circuit.
  12. Interpret simple circuit diagrams using symbols. Use symbols to draw a circuit with one battery, one bulb, a switch, and a resistor.
  13. Ohm’s Law Problems (I = V x R; Current = Voltage x Resistance)
  14. Find the resistance of a portable lantern that uses a 24 V power supply and draws a current of 0.80 A.
  15. The current in a resistor is 0.50 A when connected across a voltage of 120 V. What is the resistance?
  16. The current in a handheld video game is 0.50 A. If the resistance of the game’s circuitry is 12 ohms, what is the voltage produced by the battery?
  17. A 1.5 V battery is connected to a small light bulb with a resistance of 3.5 ohms. What is the current in the bulb?
  18. Power Calculations. (P = V x I; Power = Voltage x Current)
  19. An electric space heater requires 29 A of 120 V current to adequately warm a room. What is the power rating of the heater?
  20. A color television has a power rating of 320 W. How much current is in the television when it is connected across 120 V.
  21. The current in the heating element of an electric iron is 5.0 A. If the iron dissipates 590 W of power, what is the voltage across it?
  22. Series vs. Parallel circuits
  23. Draw a diagram of a series circuit with 3 light bulbs.
  24. Draw a diagram of a parallel circuit with 3 light bulbs.
  25. What happens to the two circuits above if one of the light bulbs goes out?
  26. For a set voltage, the current in a wire is ______proportional to its resistance. (More current exists where resistance is ______.
  27. The resistance of a material is a property of called resistivity.
  28. Increasing the length of a wire ______the resistance.
  29. Increasing the temperature ______the resistance.
  30. Increasing the diameter of a wire ______its resistance.
  31. Unlike poles on a magnet ______and like poles on a magnet ______.
  32. To increase the strength of an electromagnet
  33. ______the number of coils
  34. ______the voltage
  35. The process of electromagnetic induction in electric generators converts ______energy to ______energy.
  36. Electric motors transform ______energy to ______energy.