PHYSICSGOHS

SEMESTER II MIDTERM REVIEW-ANSWERS

  1. X-rays, visible light, microwaves, and all other types of electromagnetic waves are all what type of wave?
  2. Transverse
  3. Sound waves and waves travelling along a spring are what type of wave?
  4. Longitudinal, mechanical, compression
  5. What is the wave speed equation?
  6. v = fλ
  7. A tuning fork is used to produce sound waves with a frequency of 440 hertz. The waves travel through the air at 344 m/s. What is the wavelength of the sound waves?
  8. v = fλ
  9. λ = v/f
  10. λ = 344/440 = 0.78m/s
  11. John shakes the end of a rope with a frequency of 1.5 Hz, causing waves with a wavelength of 0.8 m to travel along the rope. What is the velocity of the waves?
  12. v = fλ
  13. v = (1.5)(0.8) = 1.2m/s
  14. What is the wavelength of a 264-Hz sound wave when the speed of sound is 345 m/s?
  15. v = fλ
  16. λ = v/f
  17. λ = 345/264 = 1.31m/s
  18. Why can no one hear Kylee scream in space?
  19. Sound waves require a medium to travel through
  20. What two types of waves lie on either side of visible light in the electromagnetic spectrum?
  21. Infrared, ultraviolet
  22. What do all electromagnetic waves have in common?
  23. Travel at speed of light, 3x108 m/s
  24. What wave phenomenon explains why things appear to be in a different place under water?
  25. Refraction
  26. Tim sprains his ankle during practice shortly after Lennon takes a hockey puck to the nose. As the ambulance is driving away from Lennon and towards Tim, how does the siren sound to each of them? What is the name of this phenomenon?
  27. Lennon hears a lower frequency than the ambulance is emitting, Tim hears a higher one. Doppler Effect.
  1. Waves carry ______from one place to another.
  2. Energy
  3. What are the two type of wave interference?
  4. Constructive and destructive
  5. Compare the momentum of two hobos riding on a railcar if the two are different masses.
  6. The bigger hobo will have a greater momentum since they are traveling the same speed.
  7. Make a comparison of a rock climber’s momentum as she climbs up the rock compared to repelling down the rock.
  8. She will have a greater momentum repelling down since she is moving faster down than she was moving up.
  9. What is impulse? How is it represented?
  10. Impulse is the change in momentum. It is F∆t.
  11. Give three examples where change in momentum is easy to observe and three when change in momentum is not easy to observe.
  12. Easy to observe: baseball hitting a bat; car hitting a wall; stopping at the end of a Montezuma’s Revenge at Knott’s
  13. Not easy to observe: baseball traveling through air; car hitting a fly; plane flying through a cloud
  14. A bird flies into a classroom and anxiously tries to fly out of the room as it slams into the window falling unconscious to the counter top. Describe the bird’s change in momentum.
  15. The bird’s has initial momentum and it’s final momentum is zero!
  16. In their dance routine Hulk Hogan and his partner, Avril Lavigne, push off each other as they do the tango. Compare and contrast each person’s momentum.
  17. They have equal but opposite momentum. Avril will only be moving faster than Hulk.
  1. What are the different types of collisions? Explain and give example of each.

  1. A deer with a mass of 146 kg is running head-on toward you with a speed of 17 m/s. You are going north. Find the momentum of the deer.
  2. 2500 kgm/s to the south
  3. A 75.0 kg sprinter running with a velocity of 10.0 m/s slows after the finish to 8.5 m/s. What is his change in momentum?
  4. -113 km/s
  5. A 0.50 kg object is at rest. A 3.00 N force to the right acts on the object during a time interval of 1.50 s. What is the velocity of the object at the end of this interval?
  6. 9.0 m/s
  7. A 63.0 kg astronaut is on a spacewalk when the tether line to the shuttle breaks. The astronaut is able to throw a spare 10.0 kg oxygen tank in a direction away from the shuttle with a speed of 12.0 m/s, propelling the astronaut back to the shuttle. Assuming that the astronaut starts from rest with respect to the shuttle, find the astronaut’s final speed with respect to the shuttle after the tank is thrown.
  8. 1.9 m/s
  9. A 1500 kg car traveling at 15.0 m/s to the south collides with a 4500 kg truck that is initially at rest at a stoplight. The car and truck stick together and move together after the collision. What is the final velocity of the two-vehicle mass?
  10. 3.8 m/s to the south