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translation motion rotation motion

Equation of motion Equation of motion
S  S  t     t

linear speed Angular speed
dS d
v   
dt dt

linear acceleration angular acceleration

2
dv d 2 S d d 
a     
dt dt 2 dt dt 2

Uniformly accelerated Uniformly accelerated rotation

translation motion
motion
2 2
at t 
v  v  at S  v 0 t      t     0 t 
0
0
2 2

2.3 Questions

1.What's angular displacement and what rule is used to define
direction of this displacement?

2. What's angular velocity ?
3. What's rotational period ?

4. What's frequency of rotation ?
5. What's angular acceleration ?
6. What are the formulas of relationships between angular and linear
kinematic values in rotational motion?

2.4 Problems
A material point moves by a circle of 0,2 m radius according to

2
3
equation   At  Bt  Ct ,where A  3 rad , B  4 rad ,
s s 2
C  2 rad 3 .Calculate:
s
- how many N revolutions will the matrial point carry out
during 4s after state of rest;

- angular velocity:

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