Physics Test 1

Card Set Information

Physics Test 1
2012-02-06 14:15:29
Physics one physical science

Physical Science
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user apalmer on FreezingBlue Flashcards. What would you like to do?

  1. Polaris
    • North Star
    • Does not move
    • Polaris is on the same axis as the earth
  2. Retrograde Motion
    • The apparent backward motion of objects in the sky
    • Caused by the earth moving faster than other objects further away from the sun
  3. Geocentrism
    • Idea that the Earth is the center of the solar system
    • Ptolemy's Idea, Ptolematic system
    • Orbital patterns thought to be circular
  4. Heliocentrism
    • Idea that planets revolve around the sun
    • Copernicus' Idea, Copernican system
    • Orbital Patterns still thought to be circular
  5. Tycho Brahe
    • Made incredible observations with crude instruments
    • Had most advanced instruments of the time
  6. Kepler's Laws
    • Three Laws
    • 1. Paths of planets around the sun are ELIPSES with the sun as focus. (Planetary motion, Eliptical Foci)
    • 2. Planet moves slower when further away from the sun, sweeping equal amounts of area in the same amount of time.
    • 3. Time taken for 1 orbit is related to distance from the sun
  7. Gravity
    • Newton's Law
    • The FUNDAMENTAL FORCE that explains all motion that can be observed in the universe

    Acceleration due to gravity (on earth) is only in an up/down direction
  8. Gravitational Constant (G)
  9. Tides
    Gravity attractions between the sun and moon
  10. Spring Tides
    • Larger
    • At new moon and full phase
    • The sun and moon's gravity pull in the same direction
  11. Neap Tides
    • Weaker
    • Angle of gravitational pull of moon and sun is a right angle
    • 1st and 3rd quarter phases
  12. Unit system used in the United States
    British Imperial
  13. International System of Units
    • Systeme Internationale
    • S.I./ Metric System
    • Ex. Meters kilograms
  14. Motion
    • A change in position
    • Everything in the universe is in constant motion
  15. Speed
    • How fast the location of any object is changing
    • Rate of change of position
    • Instantaneous Speed: speed traveling at during one moment of time. (Ex. Spedometer in car)
    • Scalar quantity
  16. Scalar Quantity
    • A quantity at wich only magnitude is specified
    • Time, mass, speed, temperature
  17. Vector Quantity
    • A quantity in which both magnitude and direction is specified
    • Velocity, Acceleration, Weight (Gravity too)
  18. Math with Vectors
    • Represented by an arrow
    • Length of arrow = magnitude of vector
    • Arrow head points in the direction of the vector
  19. Velocity with Vectors
    Have direction: North, east, 45 degrees
  20. Acceleration
    • Rate of change of velocity
    • Acceleration is negative if it is opposite to the motion of the object
  21. Changes In Velocity
    • If it increases in magnitude (5 m/s -> 15 m/s)
    • Decreases in magnitude
    • Changes direction
  22. Galileo's Experiments
    • Velocity of a falling object is proportional to the length of time that the object has been falling
    • In the abscence of air, all things fall the same rate
  23. Newton (Person)
    • Wanted to know why things move
    • Developed the idea of FORCE
  24. Force
    • A pull or push constitutes a force
    • Units: Newton (N) or Pound (lb)
    • Vector Quantity
    • At any time, there may be several forces acting on an object: Net Force
  25. Weight
    Force due to gravity
  26. Uniform motion
    • Object moves with constant velocity
    • Net Force = 0
  27. Accelerated motion
    • Velocity isn't constant... object accelerates
    • Net force does not equal 0
  28. Inertia
    • Object's resistance to change and motion
    • Greater mass = greater inertia
  29. Newton's Laws
    • 1. Law of Inertia: if Fnet= 0, a body at rest will stay at rest
    • 2. If there is a net force, the object accelerates
    • 3. Action-reaction: For every action, there is equal opposite reaction. Forces come in pairs.
  30. Friction
    • Static Friction: Non-moving
    • Kinetic friction-moving
    • In order to get an object moving we must overcome static friction
    • Rougher materials have greater frictional forces
    • Frictional forces always oppose the motion of the object
  31. Air Resistance
    • Friction during free fall means net force is reduced
    • As velocity increases, so does frictional force
    • Frictional force= weight force, net force=0
  32. Terminal Velocity
    An object in freefall will fall at a constant velocity when air resistance is involved
  33. Centripetal force
    • "Center seeking" force
    • The direction is always toward the center of any curved pattern
    • Changing in direction... accelerate.
    • In circular motion, there is always a different velocity (vector, changing direction), but the speed (scalar) remains constant
  34. Law of Gravity
    • The gravitational force of attraction between two objects
  35. Work
    • Done whenever a force causes a motion or a change in motion
    • Scalar quantity
    • W= fd (F=ma)
    • Work against Gravity: Wg=mgh
    • Something has to move
    • Force must be the force along the direction of motion
    • Unit: Nm or Joule
  36. Energy
    • The ability to do Work
    • Work done = energy used
  37. Power
    • The rate at which work is done
    • Unit: J/S or 1 Watt
    • Watts over time
  38. Kinetic energy
    • Energy an object has due to motion
    • No velocity, no KE
    • Larger mass or velocity, larger KE
    • Double Velocity, KE increases 4x

  39. Potential Energy
    • Gravitational Energy/ Gravitational Potential Energy
    • Energy an object has due to its position above the ground
    • GPE= mgh
  40. Magnetic Potential Energy
    Due to object's position in a magnetic feild
  41. Conservation of Energy
    May change from one form to another, but the total amount of energy in the universe is constant

What would you like to do?

Home > Flashcards > Print Preview