Class 6 physics, chapter force, 3 lectures in total for teaching purpose

4. A body is said to be at rest if it does
not change its position with time with
respect to its surroundings.

7. A body is said to be in the state of
motion if it changes its position with
time with respect to its surroundings.

10. • State of Rest
• State of motion
• Push and Pull

11. • Understanding what is Force and its
definition
Effects of Force
• Types of Forces

15. A body is said to be at rest if it does
not change its position with time with
respect to its surroundings.

18. A body is said to be in the state of motion
if it changes its position with time with
respect to its surroundings.

22. Force is a cause (a push, pull, stretch or squeeze)
which changes or tends to change the state of rest
or the state of uniform motion, or direction of
motion, or the shape and size of a body.

23. The formula of force is defined by Newton's
second law of motion: Force exerted by an object
equals mass times acceleration of that object:
F = m ⨉ a.

25. 1. A force can change the shape or size of an object

26. 2. A force can make a stationary object move.

27. 3. A force can change the speed of a moving object

28. 4. A force can change the direction of a moving object

29. 5. A force can stop a moving object

30. FORCE
CONTACT
FORCE
FRICTION TENSION
NON -
CONTACT
FORCE
ECLECTRO -
STATIC FORCE
MAGNTIC
FORCE

31. 1. Normal reaction Force
Every action has an equal and opposite reaction

32. 2. Tension

33. 3. Muscular Force

34. 4. Collision Force

35. 5. Frictional Force

36. Reducing Frictional Force

37. Reducing Frictional Force

38. 1. Magnetic Force

39. 1. Magnetic Force

40. 2. Electrostatic Force

41. 3. Gravitational Force

42. • Understanding what is Force and its
definition
Effects of Force
• Types of Forces

45. • Understanding what is Force and its definition
Effects of Force
• Types of Forces

48. Force is a cause (a push, pull, stretch or squeeze)
which changes or tends to change the state of rest
or the state of uniform motion, or direction of
motion, or the shape and size of a body.

50. 1. A force can change the shape or size of an object

51. 2. A force can make a stationary object move.

52. 3. A force can change the speed of a moving object

53. 4. A force can change the direction of a moving object

54. 5. A force can stop a moving object

55. FORCE
CONTACT
FORCE
FRICTION TENSION
NON -
CONTACT
FORCE
ECLECTRO -
STATIC FORCE
MAGNTIC
FORCE

56. 1. Normal reaction Force
Every action has an equal and opposite reaction

57. 2. Tension

58. 3. Muscular Force

59. 4. Collision Force

60. 5. Frictional Force

61. Reducing Frictional Force

62. Reducing Frictional Force

63. 1. Magnetic Force

64. 1. Magnetic Force

65. 2. Electrostatic Force

66. 3. Gravitational Force

68. • Unit of mass and weight
Relationship between units of forces
• Direction and magnitude of Forces
• Net effect and measurement of force
• Some definitions and concepts

73. If two or more forces act in the same
direction, they add up to give a
resultant force in the same direction.

75. Thus, if the two forces acting on a body
are equal in magnitude, but opposite in
direction, the net force on the body is
zero

78. Two substances which when rubbed together
produce electric charge.

79. Definition of Contact Forces
When the force applied on an object is in direct
contact i.e., the object with which we apply the
force and the object on which the force is applied
are in direct contact, then we call it a contact force.

80. Definition of Non-Contact Forces
Non-contact force is also called the force acting at
a distance. When we apply a force on an object
without actual contact, it is the force acting at a
distance.

81. Definition of Gravitational Force
The force of attraction between any two objects
possessing mass is called gravitational force which
exists everywhere in the universe. The magnitude of
gravitational force between any two bodies depends
upon their masses and the distance between them.

82. Definition of Electrostatic Force
Force applied by a charged body on an another charged
or uncharged body is called electrostatic force.

83. A body is said to be stretched if the force applied on
the body increases the length of the body on which the
force is applied, i.e, the increase in the length of the
force is in the direction of applied force.
Definition of Stretch

84. A body is said to be squeezed if the force applied on
the body decreases its length or changes its
dimension.s
Definition of Squeeze

85. 1. A bullock pulling a cart
2. A crane lifting a heavy iron load
3. Weighing something on a spring balance.
4. Applying the brakes on a bicycle.
5. Picking up paper scraps with a plastic ruler.
_____________
_____________
_____________
_____________
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86. • Unit of mass and weight
Relationship between units of forces
• Direction and magnitude of Forces
• Net effect and measurement of force
• Some definitions and concepts