I.
II.
Physics Test Review - Chp. 8 and 9
Angular speed,ω
● radians per time
○ turns around circle x 2π
● finding linear speed of rotating object, v = (ω)(r)
Centripetal force
● all natural forces that make an object go in circular motion
○ Fc = (mv 2 )/r
● centripetal acceleration
○ a c
= v 2 /r
● object in orbit, driving around curved road (flat or banked), object spinning while attached to string.
III. Universal gravitation
● G = 6.67 x 10 -11 (Nm 2 )/kg 2
● F g
= G∙(m
1 m
2
)/r 2
IV. Torque
●
Force applied some distance away from a center of rotation
● eqn: τ = r∙F
● static equilibrium: torque on both sides of center of rotation must be equal
● applying torque at an angle
V. Center of gravity
● for an object to remain upright, center of gravity must act inside area of support
VI. Rotational Inertia
● dependent on mass and mass distribution, mv 2
● moment of inertia, I
VII. Angular acceleration
● change in angular speed per change in time
● linear accel. = radius of circle x angular accel.
● angular accel. = τ / I