Angular kinematics

Question 1

What is angular kinematics?

Answer 1

description of angular motion

Question 1

what is angular position

Answer 1

orientation of a line relative to another line or a plane

Question 2

what is absolute vs relative angular position?

Answer 2

in absolute the reference line/plane is fixed and in relative the line/plane is moveable

Question 3

what is a radian ?/?

Answer 3

arc length/radius

Question 4

how do u get degree to radians and radian to degrees

Answer 4

degree to radian = multiple by pi/180
radian to degree = multuply by 180/pi

Question 5

what is angular displacement and what is the symbol?

Answer 5

angular displacement is the change in absolute angular position of a rotating line
the angle formed between the final and intial position of a rotaiting line

symbol = (Δθ)

Question 6

is cw negative or positive?

Answer 6

negative

Question 7

in angular motion do we consider distance travelled and sisplacemtnt he same?

Answer 7

yes

Question 8

is angular diplacemtn the same for all points on a line?

Answer 8

yes

Question 9

linear DISTANCE (arc length) travelled be a point on a line is ____ to distance from axis of rotation and angular displacemetn in _____

Answer 9

directly porprotional, radians
l = Δθr

Question 10

How are linear displacement and linear distance different in terms of angular displacement?

Answer 10

linear distance is porpotional to angular displacement
linear displacement is NOT porportional to angular displacement

Question 11

what is a chord? What is chord length also called?

Answer 11

line joining any 2 pts on a curve - chord length = lnear displacement

Question 12

Why do we need large muscle force to produce small torque?

Answer 12

because muscles attach close to joint so have small moment arms and this os a mechanical disadvantage for torque production

Question 13

what is a mechanical disadvanatge for torque production

Answer 13

muscles attach close to joints so there is a small moment arm so large muscle force is needed to produce small torque

Question 14

Small movement near joint produces a large _____

Answer 14

linear displacement - mechanical advantage for lienar displacement

Question 15

What is a mechanical advantage for linear displacement?

Answer 15

small movement near joint produces a large linear displacement - useful for sports equipment liike hockey sticks and rackets

Question 16

State one mechanical advantage and disadvantage to
having muscle insertions close to the joint (axis of
rotation)

Answer 16

Adv - produces a great linear displacement from a small movement
disadv - requires a large msucle force to produce small torque due to small moment arm as msucle attaches very close to joint

Question 17

What is angular velocity? Vector or scalar?

Answer 17

rate of change in angular displacement/ Vector

Question 18

what is average w(ang v) important for? What is instantaneous ang v important for?

Answer 18

AVG: want to know how long it takes for something to rotate from A to B
– relevant to sports with twists/somersaults such as diving, gymnastics, figure skating
- same for all pts on a line
INSTANT: important if we want to know how fast smth is rotating at a given time.
- relevant to sports where a bat/stick/club strikes an object such as baseball, hockey, golf

Question 19

what does s represent?

Answer 19

linear speed

Question 20

what is VT

Answer 20

instantaneous tangential linear velocity

Question 21

what is a tangent?

Answer 21

line which touches a circle at only
one point and is perpendicular to the radius

Question 22

What s a mechanical advantage for linear velocity

Answer 22

Small movement near the
joint produced 8× greater
linear displacement at the
wris
- sports equipment as small movements
near axis of rotation produce large linear velocities
at business end of bat, stick, club, et

Question 23

is angulat acc a vector or scalar?

Answer 23

vector

Question 24

When does angular acceleration occur?

Answer 24

spins faster
spins slower
axis of spin changes direction

Question 25

What are the 2 types of instantanepis linear acceleration assoc w angular motion?

Answer 25

tangential acceleration
centripetal acceleration

Question 26

what is tangential acc?

Answer 26

isntantatneous lienar accelration at a tangent to the circular path

Question 27

what is centripetal acceleration?

Answer 27

linear accelrations towards the axis of rotation

Question 28

What is needed to maintain an object on a circular path?

Answer 28

centripetal - without it the object woudl travel at a tangent

Question 29

Sprinters in lanes 1 and 4 have the same ____ velocity but a different ____ velocity

Answer 29

same tangential but different centripetal

Question 30

if tangential velocity is kept constant what affect does this have on centripetal acceleration?

Answer 30

If tangential linear velocity is constant then centripetal accelration is inversely porpotional to radius - so a smaller radius means a greater centripetal acceleration

Question 31

if angular velocity is kept constant what affect does this hav eon centripetal accelraton and radius

Answer 31

centripetal acc is porportional to radius so larger adius mean great centripetal accelration when angular velocity is constant

Question 32

where is force and load on class one