1. A scalar is a number that goes with a Physics concept (mass, speed, time, Energy).  It does not have a direction associated with it.  A vector has both a number and a direction (velocity, acceleration, Force, 20 Newtons Left).
  2. Speed does not have a direction (scalar). Velocity does have a direction (vector).
  3. 5.5 m/s/s
  4. Every second, a falling object covers more distance than in the last second.
  5. Every second, a falling object will speed up (free fall)
  6. The acceleration of a freely falling object will always be 9.8 m/s/s down.
  7. Acceleration in the vertical direction: 9.8 m/s/s down. Acceleration in the horizontal direction: 0 m/s/s.
  8. The law of Inertia: An object in motion will remain in motion, and an object at rest will remain at rest, unless acted on by an outside force.
  9. F = ma
  10. Every force has an equal and opposite force (force pairs).
  11. Mass is how much “stuff” is inside an object (atoms etc…). Weight is how much the Earth pulls down on something with (its a force in Newtons).
  12. Twice the mass means it resists twice as much, so it accelerates only half as much (2.5 m/s/s).
  13. Racecar: 52,000 kgm/s versus Truck: 48,000 kgm/s
  14. Impulse is the change in momentum.  A car that crashes into another car experiences a force for a given time, which slows it down (changes its momentum).
  15. Decrease the force? Increase the time to stop.  Because in a car crash, it stops very suddenly with little time, the force is very high.
  16. Elastic: bounces: no permanent deformation, no generation of heat. Inelastic: sticks together, permanent deformation, heat is produced.
  17. 13 m/s.
  18. KE: energy of motion; PE: energy stored due to an object’s position or location
  19. The total energy will be the same throughout the fall (GPE into KE)
  20. The total energy will be the same throughout the launch (EPE into KE)
  21. Will vary… dropping a rock
  22. Will vary… throughout the flight of a car being launched into the air
  23. The car with the faster speed will have 4x the KE.
  24. Energy is never created or destroyed, but it only transforms from one form to another.
  25. When you put work into something, it transforms into energy.  Ex: Lifting a rock into the air
  26. A rotation spins around an interior point. A revolution orbits around an exterior point.
  27. Answers will vary; anything moving in a circle… whatever causes that circular motion
  28. 6.07 N forward
  29. 157.1 Watts, 110 Watts
  30. One fourth the gravity (4x weaker)
  31. One ninth the gravity (9x weaker)
  32. Four times the gravity (4x stronger)
  33. Two times the gravity (2x stronger)
  34. Three times the gravity (3x stronger)