Regents Physics Exam Prep: 101 Facts You Should Know (Part I)
Sample problems from the blue textbook.
Mechanics
1. Weight (force of gravity) decreases as you move away from the earth by distance
squared. (pg 47, # 109, # 110, # 111, # 112)
2. Mass and inertia are the same thing. (pg 37, # 57, # 58)
3. Constant velocity and zero velocity means the net force is zero and acceleration is zero.
(pg 38, # 66, # 71, pg 57, # 22)
4. Weight (in newtons) is mass x acceleration (w = mg). Mass is not weight! (pg 47, #
113-115, pg 48, #119)
5. Velocity, displacement [s], momentum, force and acceleration are vectors. (pg 27, #1, #2)
6. Speed, distance [d], time, and energy (joules) are scalar quantities. (pg 27, # 4)
7. The slope of the velocity-time graph is acceleration. (pg 28, #11, # 15, #18)
8. The area under the velocity-time graph is distance. (pg 28, # 17, pg 62, #74)
9. At zero (0) degrees two vectors have a resultant equal to their sum. At 180 degrees two
vectors have a resultant equal to their difference. From the difference to the sum is the
total range of possible resultants. (pg 34, #43 - #50)
10. Centripetal force and centripetal acceleration vectors are toward the center of the circlewhile the velocity vector is tangent to the circle. (pg 44, #99, pg 45, #105, #106)
11. An unbalanced force (object not in equilibrium) must produce acceleration. (pg 37, #60,
pg 38, #65, # 70)
12. Frictional force is equal to normal force times a coefficient of friction. (pg 60, #44)
13. The slope of the distance-time graph is velocity. (pg 27, #6, pg 29, #36)
14. An object in free-fall has an acceleration of g=9.8 m/sec2.
15. Action-reaction. (pg 39, #73, pg 57, #24)
16. An object in equilibrium has a net force of zero. (pg 57, # 23)
17. Momentum is conserved in all collision systems. (pg 53, #144, #145, #146)
18. Impulse is equal to both change in momentum and force times time. (pg 53, #139, #143,
pg 60, #48)
19. Forces in two dimensions can be decomposed into x and y components. (pg 69, #136)
20. A body on an inclined plane has a weight vector pointing straight down, a normal force
pointing perpendicular to the plane, and a force parallel to the plane. (pg 50, #127, pg 73,
#169-171)
21. For 2-dimensional projectile problems, the acceleration in the y direction is constant and
9.8 m/s^2, while the acceleration in the x-direction is zero. (pg 63, # 83-89)
22. An object that is slowing down has an acceleration vector that points in the opposite
direction from its velocity vector. (pg 28, #10, pg 29, #32)
23. Magnitude is a term used to state how large a vector quantity is.
Energy
24. Mechanical energy is the sum of the potential and kinetic energy. (pg 90, #85, pg 98,
#66)
25. Units: a = [m/sec2], F = [kg•m/sec2] (newton), work = pe= ke = [kg•m2/sec2] (joule)
26. Work equals force times distance. (pg 77, #2, #7)
27. Gravitational potential energy increases as height increases. (pg 79, #30, pg 80, #63)
28. Kinetic energy changes only if velocity changes. (pg 84, #59, #60, pg 85, #63)
29. Mechanical energy (pe + ke) does not change for a free falling mass or a swinging
pendulum. (when ignoring air friction) (pg 88, #68, #69, pg 89, # 73)
30. The force on a spring equals the elongation of the spring times the spring constant k. (pg
82, #40, #41, pg 83, # 42)
31. The potential energy stored in a spring is proportional to the elongation of the springs
squared. (pg 83, #51, #52, #53)
32. Power is the rate of change of energy. (pg 78, #17, #19)
33. The units for power are [joules/sec] or watts.