physics 1301 unit 3

- rotation motion -tangential angular velocity and acceleration-centripetal accel.-forces that cause centripetal forces-fictitious forces-banked curves

ΘΔ=

wt

conversion factor w to Θ/s

360/2(pi)rad

every portion of an object has the ___ angular velocity and acceleration because

same; bc the distance is different but the angle (ssector) is the same and thats what matters

Θ=

tan^-1(a_t/a_c) or Fgy/Fgx

constant angular accel. means

constant a_t → a is always the same

can find v using

at or regular kinematics

centripetal force is (pos or neg)

negative. Fc= -nsinΘ

banked track

min and max safe speeds are determined by Θ, friction, and radius

a_c=

-gtan(Θ) ONLY if theres no friction and car doesnt slide up or down

(general formula) a_c=

g times (sin theta plus coefficient of friction times cosine theta) divided by (cos theta MINUS coefficient of friction times sin theta)

F_c=

ma_c = (mv²)/r

sigma F_r=

-mv²/r

newtonian gravitation: F=G(m1m2)/r², r=

the distance between centers of both objects

• given surface to surface, add the radii to the total distance

force exerted by m1 on m2 is

EQUAL but in opposite direction to F exerted by m2 on m1.

linear a=

final - initial velocity over delta time

total a

vector of tangential a and centripetal a

if an object moves at constant speed,

at=0.

at changes speed

ac changes direction

on a circular path _____ change

both v and and angular acceleration change ?

force acting at an angle,

use force thats perpendicular to the door → Fsin(theta)

which angle to use for rotational equilibrium

the angle BETWEEN the force and the radius (F and r)

when mass is concentrated around hoop

it takes longer to stop because I depends on how the mass is distributed and an the location of the axis of rotation

center of mass on a symmetrical object must

lie on the axis of symmetry

the larger r is, the larger the

angular acceleration

torque

causes angular acceleration