Chapter 10&ll 质点的转动 Chapter 10 &e 11 Rotational motion Angular Quantities Torque Angular Momentum Conservation of Angular Momentum
Chapter 10&11 质点的转动 Chapter 10 & 11 Rotational Motion • Angular Quantities • Torque • Angular Momentum • Conservation of Angular Momentum
Chapter 10&ll 质点的转动 10-1.Angular Quantities(P235-237) 1.Angular position 0 p235: We measure the angular position 6 of this line relative to a fixed direction (x) △s △0 Unit of: radian(rad)弧度 0
Chapter 10&11 质点的转动 10-1. Angular Quantities (P235-237) r s = Unit of : radian( rad) 弧度 o r s x s We measure the angular position of this line relative to a fixed direction (x). 1.Angular position p235:
Chapter 10&ll 质点的转动 2. Angular Displacement(角位移):△ a body that rotates about a rotation axis, changing its angular position from 6, to 62, undergoes an angular displacement: △b=6,-01 Where△ e is positive for counterclockwise(逆时 针) rotation and negative for clockwise.(顺时针) rotation Always: 6=60
Chapter 10&11 质点的转动 2.Angular Displacement(角位移): ●Where is positive for counterclockwise（逆时 针） rotation and negative for clockwise（顺时针） rotation. Always: = (t) a body that rotates about a rotation axis, changing its angular position from 1 to 2 , undergoes an angular displacement: = 2 −1
Chapter 10&ll 质点的转动 3.Angular velocity p236: P(△n △bd6 0= lim Q△ 4→>0△tdt The magnitude of the bodys angular velocity is the angular speed. 方向:满足右手定则,沿刚体转动方向右旋大拇指指 Right-hand-rule: When the fingers of the right hand are curled around the rotation axis and point in the direction of the rotation, then the thumb points in the direction of
Chapter 10&11 质点的转动 x y o P(t) P0 r t t t d d lim 0 = = → 3.Angular Velocity p236: The magnitude of the body’s angular velocity is the angular speed. 方向：满足右手定则，沿刚体转动方向右旋大拇指指 向。 Right-hand-rule: When the fingers of the right hand are curled around the rotation axis and point in the direction of the rotation, then the thumb points in the direction of . (p241)
Chapter 10&ll 质点的转动 4.Angular Acceleration 237 TThe limit of the ratio as time interval approaches zero. △od a=m 4→0△tdt
Chapter 10&11 质点的转动 t t t d d lim 0 = = → 4.Angular Acceleration p237: The limit of the ratio as time interval approaches zero