This document discusses key concepts related to rotational motion including: 1. Rotational motion involves rotation around an axis of rotation. Rigid bodies can experience both translational and rotational motion when torque is applied. 2. Key terms related to rotational motion include angular displacement, angular velocity, angular acceleration, moment of inertia, and torque. These terms are used to describe the rotational equivalent of displacement, velocity, acceleration, mass, and force for linear motion. 3. Rotational kinematic equations can be used to relate angular displacement, angular velocity, angular acceleration, and time for rotational motion, similar to the linear kinematic equations for translational motion. Concepts like angular momentum and rotational kinetic energy also have analogous

1. Rotational motion

2. ?

3. Rigid Body) Torque

4. angular speed )
ω
t
ω
t

5. angular velocity )
 
angular displacement )


t

)


6. angular acceleration )



t



7. s
v
t t
v
a
t t
t v u at
0
1 2 1 2
s ut at
0t t 2
2
2 2 v2 u 2 2as
0 2
u v
0
s t
t 2
2

8. 1.
2.

9. 3.
4.

10. 5.
6.

11. 7.
0 t
5 2 10
25rad / s

12. 8.
0
t
40 0
10
4rad / s 2
0
t
2
0 40
10
2
200rad

13. 9.
2 2
0 2
2
108 02 2 234
11664
24.92rad / s 2
468

14. 10.
rpm s
(ก)
(ข)
(ค) cm
t=0

15. 4 0.20 kg
11. 0.40 m
4
1
1
( ) (O)
( ) AB
(0.064 kg⋅m2,0.032 kg⋅m2)

16. 0.20 kg 4
12. xyz
2 4
x, y z
2

17. 8 m
13.
3
3
z IZ 4ma 2
(ก)
(ข) I3,7 8ma2
z 3 7

18. 14.
y
rad/s
1 2
K I
2
1 2
K mi vi
2
(ก)
( ข)

19. 15.
xy
xy z
rad/s
m2
z
kg ⋅ ,

20. 16.
y x
2.00 rad/s
1 2
(ก) K
2
I x
1 2
K mi vi
2
( ข) tangential speed)

21. 17. M m
L
18. m2 kg ⋅

22. 19. M
1 1
I
yy 2
M 2 , I y
3
M 2 y'
20.  M R
z

23. 20.
1 2 2
R2 R1 I R1 R2
2
, M

24. 21. m1 m2
M R
m1
m2
m1 m2 2 m1 m2 gh v
v ,
1 R
m1 m2 m
2
h

25. 22. M l
3g / l , v 3gl , 3g / 2l, a 3g / 4

26. 23. kg cm
kg
49 rad / s 2

27. 24. N
M = 4.00 kg cm
rad/s 1.10 m N
fr
s

28. 25.
N

29. 26. R0 M
H
10
v gh
7

30. 27.

31. 28.
F fr F fr
F fr FN F fr s FN
10 2
v gh , F fr Mg sin
7 7

32. 29.
F1 F2
a= 0.5g
M = 1200 kg
m
CM
cm

33. 30. Yo-Yo
M R
(ก)
(ข)

34. 31.
M R
v0 t=0

35. 32. Atwood Machine m1 m2
R0 m1 m2
I

36. 33. Torque on imbalanced system, net

37. 34. m v
R0
M

38. 35.
36.
rad/s rad/s
ก) s2 rad)
ข) rad/ )

39. 37.
ก.
ข.
38. cm
ก)
ข)
ค) s2
rad, 44 rad/s, 4.4 rad/ )

40. 39. cm
2
ก)
ข)
ค) (45 rad, 14 rad/s, 4.2 m/s)
2
40. kg.m
N.m)

41. 41. ABC A, B, C
g, 30 g, g
ก) A ABC
ข) 2 BC 2
(1.48×10−4 kg⋅m , 3.2×10−5 kg⋅m )
42. cm kg
2
kg.m /s
2
m/s
kg.m ,
115 J)

42. 43.
kg
m
2
cm kg.m
ก)
44. kg
ข)
cm
2 2
mr m/s
5
(3.5 m)

43. 45. (En 41)
2 2 2 2
46. (En 44/2)
1. 0.05 kg.m 2. 0.09 kg.m 3. 0.12 kg.m 4. 1.20 kg.m
2
kg.m/s
F
m)

44. 47.
2
2
48. (En 40)
rad/s )
rad/s)

45. 49.
J)
50. (En 40)
AB 10 J)

46. 51.
9.0 10 4kg m 2
5.38 10 3 J
52. (En 41)
m/s
m)

47. http://phchitchai.wbvschool.net/lesson/07_RotationMotion/Animation/index.html
http://phchitchai.wbvschool.net/lesson/07_RotationMotion/Mindmap/index.html
http://phchitchai.wbvschool.net/lesson/07_RotationMotion/Exam/index.html
http://www.rmutphysics.com/charud/entrance/physics1/rotation/index1.html
http://www.rmutphysics.com/charud/entrance/physics1/rotation/index2.html
http://www.rmutphysics.com/charud/entrance/physics1/rotation/index3.html

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