1. kinematics Speed, velocity and acceleration
Graphical analysis of motion
Free-fall
Kinematics

2. Distance & displacement
Kinematics

3. Distance & displacement
Distance is the total length travel irrespective of the direction of motion. It is a scalar quantity.
Displacement is the distance moved in a particular direction. It is a vector quantity.
Kinematics

4. Actual length covered by moving body irrespective the direction
Shortest distance between initial and final position
Kinematics

5. Distance taken with consideration of direction
Aspect
Distance
Displacement
Definition
Total route by a motion
Distance taken with consideration of direction
Type of quantity
Scalar quantity
Vector quantity
SI Unit
metre / m
Kinematics

6. Displacement example
If you walk 2 km from home to school, and 2 km back to school to home, then you have travelled a total distance of 4 km. On the other hand, as your final position is the same as your initial position, your displacement is zero.
A physics teacher walks 4 meters East, 2 meters South, 4 meters West, and finally 2 meters North.
What is the total distance travelled?
What is the boy’s displacement from P?
Kinematics

7. Speed & velocity
Kinematics

8. Speed & velocity
The speed of an object is the distance moved by the object per unit time. It also is defined as the rate of change of distance.
The common units for speed are metres per second (m s-1) and kilometres per hour ( km h-1).
Kinematics

9. This average speed is also known as the instantaneous speed. Example 2
For most journeys, speed is not constant. Normally we take the journey as a whole and calculate the average speed.
This average speed is also known as the instantaneous speed.
Example 2
If a car is taken from the garage, driven for 100 km before returning to the garage after 2 hours, what is it average speed?
Kinematics

10. Velocity is also measured in m s-1 and km h-1.
Velocity is the distance travelled per unit time in a specified direction. It is also defined as the rate of change of displacement.
Velocity is also measured in m s-1 and km h-1.
It is a vector quantity as the direction of travel is important.
Kinematics

11. Rate of change of distance Rate of change of displacement
Aspect
Speed
Velocity
Definition
Rate of change of distance
Rate of change of displacement
Type of Quantity
Scalar
Vector
Formula
= Total distance
Time
= Total displacement
time
SI Unit
metre per second / m s-1
Kinematics

12. the distance travelled by the cyclist,
Example 3
A cyclist travels 6 km due east and then makes a turn to travel a further distance of 8 km due north. The whole journey takes 2 hours. Calculate
the distance travelled by the cyclist,
the average speed of the cyclist,
the displacement of the cyclist,
the average velocity of the cyclist.
Kinematics

13. Example 4
A boy run 5 km due west and then return back to travel a further distance of 4 km before resting. The whole journey takes 1 hour. Calculate
his total distance travelled,
his average speed,
his displacement from the starting point,
his average velocity.
Kinematics

14. Example 5
A car starts from point O and moves to U, 50 m to the north in 60 s. The car then moves to B, 120 m to the west in 40 s. Finally, it stops. Calculate the:
total distance moved by the car
displacement of the car
speed of the car when it is moves to the north
velocity of the car
average speed of the car
Kinematics

15. example A car travels along the route PQRST in 30 minutes.
What is the average speed of the car?
10 km / hour
20 km / hour
30 km / hour
60 km / hour
Kinematics

16. A man crosses a road 8.0 m wide at a speed of 2.0 m / s.
How long does the man take to cross the road?
4.0 s
6.0 s
10 s
16 s
Kinematics

17. A child is standing on the platform of a station, watching the trains.
A train travelling at 30 m / s takes 3 s to pass the child.
What is the length of the train?
10 m
30 m
90 m
270 m
Kinematics

18. A car driver takes a total of two hours to make a journey of 75 km
A car driver takes a total of two hours to make a journey of 75 km. She has a coffee break of half an hour and spends a quarter of an hour stationary in a traffic jam.
At what average speed must she travel during the rest of the time if she wants to complete the journey in the two hours?
38 km/ h
50 km/ h
60 km/ h
75 km/ h
Kinematics

19. What is the average speed of the car for the whole journey?
A car takes 1 hour to travel 100 km along a main road and then ½ hour to travel 20 km along a side road.
What is the average speed of the car for the whole journey?
60 km / h
70 km / h
80 km / h
100 km / h
Kinematics

20. 0625/01/O/N/08 Q3
A car travels at various speeds during a short journey.
The table shows the distances travelled and the time taken during each of four stages P, Q, R and S.
Kinematics

21. During which two stages is the car travelling at the same speed?
P and Q
P and S
Q and R
R and S
Kinematics

22. 0625/01/O/N/03 Q4
A train travels along a track from Aytown to Beetown. The map shows the route.
Kinematics

23. How long does the journey take?
The distance travelled by the train between the towns is 210 km. It moves at an average speed of 70 km/ h.
How long does the journey take?
Kinematics

24. 0625/01/M/J/08 Q3
The circuit of a motor racing track is 3 km in length. In a race, a car goes 25 times round the circuit in 30 minutes.
What is the average speed of the car?
75 km / hour
90 km / hour
150 km / hour
750 km / hour
Kinematics

25. 0625/01/M/J/03 Q4
A tunnel has a length of 50 km. A car takes 20 min to travel between the two ends of the tunnel.
What is the average speed of the car?
2.5 km/ h
16.6 km/ h
150 km/ h
1000 km/ h
Kinematics

26. Acceleration
Kinematics

27. acceleration
Acceleration is defined as the rate of change of velocity.
The SI unit for acceleration is m s-2.
Acceleration is a vector quantity. The direction of acceleration is the direction of change in velocity.
Kinematics

28. There is acceleration only when velocity changes.
If velocity is constant throughout, there is no acceleration.
If the velocity is increasing, the object is said to be accelerating.
If the velocity is decreasing, then the object is said to have negative acceleration or deceleration or retardation.
A body is said to move with uniform acceleration if its rate of change of velocity with time is constant.
Kinematics

29. example
A car accelerates from rest to 50 ms-1 in 10 s. Calculate the acceleration of the car.
A car is uniformly retarded and brought to rest from a speed of 108 ms-1 in 15 s. Find its acceleration.
The driver of a car brakes when the car is travelling at 30 ms-1. The velocity of the car is reduced to 10 ms-1 after 5 s. What is its average acceleration?
Kinematics

30. If a car can accelerate at 3
If a car can accelerate at 3.2 ms-2, how long will it take to speed up from 15 ms-1 to 22 ms-1?
How fast does a motorcycle travel if it starts at rest and is going 22 ms-1 after 5 seconds?
What is the acceleration of a car that speeds up from 12 ms-1 to 30 ms-1 in 15 seconds?
A truck travelling at 25 ms-1 puts its brakes on for 4 s. This produces a retardation of 2 ms-2. What does the truck’s velocity drop to?
Kinematics

31. How fast does a car travel if it is going 4 m/s and accelerates at 3
How fast does a car travel if it is going 4 m/s and accelerates at 3.5 m/s2 for 5 seconds?
If a car is going at 12 m/s, how long will it take to reach a speed of 26 m/s if it accelerates at 2.2 m/s2?
A car moving along a straight level road has an initial speed of 3 m/s and its acceleration is 2 m/s2. What is the speed of the car after 5 s?
Kinematics

32. A car sets off from a traffic lights
A car sets off from a traffic lights. It reaches a speed of 27 m/s in 18 s. What is its acceleration?
A train, initially moving at 12 m/s, speeds up to 36 m/s in 120 s. What is its acceleration?
Kinematics

33. Ticker tape diagrams
Kinematics

34. A common way of analyzing the motion of objects in physics labs is to perform a ticker tape analysis.
Kinematics

35. One tick is equal to 1/50 s or 0.02 s.
A ticker tape timer consists of an electrical vibrator which vibrates 50 times per second. 
The time interval between two adjacent dots on the ticker-tape is called one tick. 
One tick is equal to 1/50 s or 0.02 s.
Kinematics

36. example
Find the number of ticks and the time interval between the first dot and the last dot on each of the ticker tapes below. The frequency of the ticker timer is equal to 50Hz.
Kinematics

37. The trail of dots provides a history of the object's motion and is therefore a representation of the object's motion.
The distance between dots on a ticker tape represents the object's position change during that time interval.
A large distance between dots indicates that the object was moving fast during that time interval.
A small distance between dots means the object was moving slow during that time interval.
Kinematics

38. Pattern
Explanations
The distance between the dots is the same. It shows that the object is moving with constant speed.
The distance between the dots is short. It shows that the speed of the object is low.
The distance between the dots is far. It shows that the object is moving at a high speed
Kinematics

39. The analysis of a ticker tape diagram will also reveal if the object is moving with a constant velocity or with a changing velocity (accelerating).
Kinematics

40. Pattern
Explanations
The distance between the dots is increased. It shows that the speed of the object increases.
The distance between the dots is decreased. It shows that the speed of the object decreases.
Kinematics

41. Displacement-time graph
Kinematics

42. s =
10 m
Kinematics

43. At rest
Gradient = 0 Hence, velocity = 0
Kinematics

44. s =
0 m
10 m
20 m
30 m
40 m
50 m
Kinematics

45. uniform velocity Gradient is constant, Hence, velocity is uniform
Kinematics

46. s =
0 m
2 m
8 m
18 m
32 m
50 m
Kinematics

47. acceleration Gradient is increasing Hence velocity is increasing.
Kinematics

48. deceleration Gradient is decreasing Hence velocity is decreasing.
Kinematics

49. Gradient of displacement-time graph
𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑦−𝑎𝑥𝑖𝑠 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑥−𝑎𝑥𝑖𝑠 ∆𝑦
y-axis
𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑑𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡 𝑡𝑖𝑚𝑒
𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡=𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑜𝑓 𝑜𝑏𝑗𝑒𝑐𝑡 ∆𝑥
x-axis
Kinematics

50. Velocity-time graph
Kinematics

51. s =
0 m
Kinematics

52. At rest
Kinematics

53. s =
0 m
10 m
20 m
30 m
40 m
50 m
Kinematics

54. uniform velocity
Kinematics

55. s =
0 m
2 m
8 m
18 m
32 m
50 m
Kinematics

56. Uniform acceleration
Kinematics

57. Uniform deceleration
Kinematics

58. Non-uniform acceleration
Increasing acceleration
Kinematics

59. Non- uniform deceleration
Decreasing acceleration
Kinematics

60. Gradient of velocity-time graph
𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑦−𝑎𝑥𝑖𝑠 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑥−𝑎𝑥𝑖𝑠 ∆𝑦
y-axis
𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡= 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑡𝑖𝑚𝑒
𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡=𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑜𝑏𝑗𝑒𝑐𝑡 ∆𝑥
x-axis
Kinematics

61. Area under the graph of velocity-time graph
𝐴𝑟𝑒𝑎 𝑜𝑓 𝑅𝑒𝑐𝑡𝑎𝑛𝑔𝑙𝑒=𝑊𝑖𝑑𝑡ℎ×𝐿𝑒𝑛𝑔𝑡ℎ
width
𝐴𝑟𝑒𝑎 𝑜𝑓 𝑅𝑒𝑐𝑡𝑎𝑛𝑔𝑙𝑒=𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦×𝑇𝑖𝑚𝑒
𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦×𝑇𝑖𝑚𝑒=𝐷𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡
𝐴𝑟𝑒𝑎 𝑢𝑛𝑑𝑒𝑟 𝑡ℎ𝑒 𝑔𝑟𝑎𝑝ℎ=𝐷𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡
length
Kinematics

62. Interpreting graph From the displacement-time graph
Its gradient gives the velocity of the moving object.
From velocity-time graph
Its gradient gives the acceleration of the moving object.
The area under the graph gives the distance travelled by the object
Kinematics

63. Example 1
Figure below shows the velocity a cyclist as she cycled through a town.
Kinematics

64. What was the cyclist’s velocity after 60 s?
How long did she have to wait at the traffic light?
Which was larger, her deceleration as she stopped at the traffic lights, or her acceleration when she started again? Explain your answer.
What is her total distance travelled for 120 s of the journey?
Kinematics

65. Example 2
Figure below represents graphically the velocity of a bus moving along a straight road over a period of time.
Kinematics

66. What does the portion of the graph between 0 and A indicate?
What can you say about the motion of the bus between B and C?
What is the acceleration of the bus between C and D?
What is the total distance traveled by the bus in 100 s?
What is the average velocity of the bus?
Kinematics

67. Example 3
The graph below shows how the velocity of a certain body varies with time, t.
Kinematics

68. Calculate the acceleration during the first 10 s shown on the graph.
During the period t = 30 s to t = 45 s the body decelerates uniformly to rest. Complete the graph and obtain the velocity of the body when t = 38 s.
Obtain the distance travelled by the body during the period t = 30 s and t = 45 s.
Kinematics

69. Example 4
A cyclist started from rest achieved a speed of 10 m s-1 in 5 s. He then cycled at this speed constantly for the next 15 s. Finally he decelerate to complete his 30 s journey.
Sketch a velocity-time graph for the whole journey?
Calculate his deceleration in the last 10 seconds of the journey.
Calculate the distance that he travelled during the journey.
Kinematics

70. velocity (m/s) 10 5 20 30
time (s)
Kinematics

71. 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛=𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡 𝑜𝑓 𝑔𝑟𝑎𝑝ℎ= 𝑦 2 − 𝑦 1 𝑥 2 − 𝑥 1 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 10−0 20−30 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 10 −10 =−1 𝑚/ 𝑠 2
Kinematics

72. 𝑡𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑=𝑎𝑟𝑒𝑎 𝑢𝑛𝑑𝑒𝑟 𝑔𝑟𝑎𝑝ℎ 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (15+30)(10) 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (45)(10)=225 𝑚
Kinematics

73. Example 5
A locomotive pulling a train out from one station travels along a straight horizontal track towards another station. The following describe the velocity of the train varies with time over the whole journey.
It started from rest and gain a speed of 40 ms-1 in 2 s.
It then travel with this speed constantly for 10 s.
Finally it decelerates and reach the other station within 2 s.
Kinematics

74. Example 5 Using the information given
Sketch a velocity-time graph for this journey.
Find
the acceleration of the train in the first 2 s.
the total distance travel between the two stations.
the average velocity of the train.
Kinematics

75. velocity (m/s) 40 2 12 14
time (s)
Kinematics

76. 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛=𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡 𝑜𝑓 𝑔𝑟𝑎𝑝ℎ= 𝑦 2 − 𝑦 1 𝑥 2 − 𝑥 1 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 40−0 2−0 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 40 2 =20 𝑚/ 𝑠 2
Kinematics

77. 𝑡𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑=𝑎𝑟𝑒𝑎 𝑢𝑛𝑑𝑒𝑟 𝑔𝑟𝑎𝑝ℎ 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (14+10)(40) 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑= 1 2 (24)(40)=480 𝑚
Kinematics

78. 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦= 𝑡𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑑 𝑡𝑜𝑡𝑎𝑙 𝑡𝑖𝑚𝑒 𝑡𝑎𝑘𝑒𝑛 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦= 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦=34.3 𝑚/𝑠
Kinematics

79. What must change when a body is accelerating?
the force acting on the body
the mass of the body
the speed of the body
the velocity of the body
Kinematics

80. Which of the following defines acceleration?
Kinematics

81. Which quantity X is calculated using this equation?
acceleration
average velocity
distance travelled
speed
Kinematics

82. A car is brought to rest in 5 s from a speed of 10 m / s.
What is the average deceleration of the car?
0.5 m / s2
2 m / s2
15 m / s2
50 m / s2
Kinematics

83. A tennis player hits a ball over the net.
Kinematics

84. In which position is the ball accelerating?
P and Q only
P and R only
Q and R only
P, Q and R
Kinematics

85. The diagram shows a strip of paper tape that has been pulled under a vibrating arm by an object moving at constant speed. The arm was vibrating regularly, making 50 dots per second.
Kinematics

86. What was the speed of the object?
2.0 cm / s
5.0 cm / s
100 cm / s
200 cm / s
Kinematics

87. Which speed / time graph applies to an object at rest?
Kinematics

88. B The speed-time graph shown is for a bus travelling between stops.
Where on the graph is the acceleration of the bus the greatest? B
Kinematics

89. A skier is travelling downhill
A skier is travelling downhill. The acceleration on hard snow is 4 m / s2 and on soft snow is 2 m / s2.
Which graph shows the motion of the skier when moving from hard snow to soft snow?
Kinematics

90. C
Kinematics

91. The graph shows the speed of a car as it accelerates from rest.
During part of this time the acceleration is uniform.
Kinematics

92. What is the size of this uniform acceleration?
5 m/s2
6 m/s2
10 m/s2
20 m/s2
Kinematics

93. The diagram shows a speed-time graph for a body moving with constant acceleration.
Kinematics

94. What is represented by the shaded area under the graph?
acceleration
distance
speed
time
Kinematics

95. The graph illustrates the motion of an object.
Kinematics

96. Which feature of the graph represents the distance travelled by the object whilst moving at a constant speed?
area S
area S + area T
area T
the gradient at point X
Kinematics

97. A cyclist is riding along a road when an animal runs in front of him
A cyclist is riding along a road when an animal runs in front of him. The graph shows the cyclist’s motion. He sees the animal at P, starts to brake at Q and stops at R.
Kinematics

98. What is used to find the distance travelled after he applies the brakes?
the area under line PQ
the area under line QR
the gradient of line PQ
the gradient of line QR
Kinematics

99. The diagram shows the speed-time graph for an object moving at constant speed.
Kinematics

100. What is the distance travelled by the object in the first 3 s?
1.5 m
2.0 m
3.0 m
6.0 m
Kinematics

101. A car accelerates from traffic lights
A car accelerates from traffic lights. The graph shows how the car’s speed changes with time.
Kinematics

102. How far does the car travel before it reaches a steady speed?
10 m
20 m
100 m
200 m
Kinematics

103. The graph represents the movement of a body accelerating from rest.
Kinematics

104. After 5 seconds how far has the body moved?
Kinematics

105. The graph shows the movement of a car over a period of 50 s.
Kinematics

106. What was the distance travelled by the car during the time when it was moving at a steady speed?
Kinematics

107. The graph shows the movement of a car over a period of 50 s.
Kinematics

108. What was the distance travelled by the car while its speed was increasing?
10 m
20 m
100 m
200 m
Kinematics

109. The graph represents part of the journey of a car.
Kinematics

110. What distance does the car travel during this part of the journey?
150 m
300 m
600 m
1200 m
Kinematics

111. question 1
Kinematics

112. Question 2
Kinematics

113. Question 3
Kinematics

114. Question 4
Kinematics

115. Question 5
Kinematics

116. Question 6
Kinematics

117. Free fall
Kinematics

118. Falling freely
A free falling object is an object that is falling under the sole influence of gravity.
Any object that is being acted upon only by the force of gravity is said to be in a state of free fall.
Kinematics

119. There are three important motion characteristics that are true of free- falling objects:
Free-falling objects do not encounter air resistance.
All free-falling objects (on Earth) accelerate downwards at a rate of 9.8 m/s2 (often approximated as 10 m/s2)
Not affected by mass and shape of the object.
Kinematics

120. Velocity
Time
Kinematics

121. SKYDIVING
At the start of his jump the air resistance is zero so he accelerate downwards.
Kinematics

122. As his speed increases his air resistance will also increase
SKYDIVING
As his speed increases his air resistance will also increase
Kinematics

123. SKYDIVING
Eventually the air resistance will be big enough to balance the skydiver’s weight.
Kinematics

124. How the forces change with time.
KEY
Gravity
(constant value & always present…weight)
Air resistance
(friction)
Net force
(acceleration OR changing velocity)

125. The size of the air resistance on an object depends on the area of the object and its speed;
the larger the area, the larger the air resistance.
the faster the speed, the larger the air resistance.
Kinematics

126. skydiving
When he opens his parachute the air resistance suddenly increases, causing him to start slow down.
Kinematics

127. skydiving
Because he is slowing down his air resistance will decrease until it balances his weight. The skydiver has now reached a new, lower terminal velocity.
Kinematics

128. Velocity-time graph for the sky diver
Parachute opens – diver slows down
Speed increases…
Terminal velocity reached…
Velocity
Diver hits the ground
New, lower terminal velocity reached
Time

129. A small steel ball is dropped from a low balcony.
Ignoring air resistance, which statement describes its motion?
It falls with constant acceleration.
It falls with constant speed.
It falls with decreasing acceleration.
It falls with decreasing speed.
Kinematics

130. C A student drops a table-tennis ball in air.
What happens to the velocity and to the acceleration of the ball during the first few seconds after release? C
Kinematics

131. Two stones of different weight fall at the same time from a table
Two stones of different weight fall at the same time from a table. Air resistance may be ignored.
What will happen and why? A
Kinematics

132. The three balls shown are dropped from a bench.
Which balls have the same acceleration?
aluminium and lead only
aluminium and wood only
lead and wood only
aluminium, lead and wood
Kinematics

133. Which graph shows the motion of a heavy, steel ball falling from a height of 2 m?
Kinematics

134. A stone falls freely from the top of a cliff into the sea
A stone falls freely from the top of a cliff into the sea. Air resistance may be ignored.
Which graph shows how the acceleration of the stone varies with time as it falls? D
Kinematics

135. An object is falling under gravity with terminal velocity.
What is happening to its speed?
It is decreasing to a lower value.
It is decreasing to zero.
It is increasing.
It is staying constant.
Kinematics

136. At which position does she have terminal velocity?
The diagrams show a parachutist in four positions after she jumps from a high balloon.
At which position does she have terminal velocity? C
Kinematics

137. Which graph represents the motion of a body falling vertically that reaches a terminal velocity?
Kinematics

138. The speed-time graph for a falling skydiver is shown below
The speed-time graph for a falling skydiver is shown below. The skydiver alters his fall first by spreading his arms and legs and then by using a parachute.
Which part of the graph shows the diver falling with terminal velocity? D
Kinematics

139. Question 1 (a) (i) weight or gravity (ii)
air resistance or drag or friction
(b)
(i)
9.8 m/s2 or 10 m/s2
(ii)
air resistance increases to oppose gravity
or air resistance increases as speed increases
(iii)
air resistance = weight
or downward force balances upward force
or no resultant force
Kinematics

140. Question 2 (a) (i) 9.8 m/s2 or 10 m/s2 (b) (i) air resistance = weight
or downward force balances upward force
or no resultant force
(ii)
weight larger than air resistance
or downward force greater than upward force
(c)
coin and paper accelerate at 10 m/s2
hit bottom at the same time
not fall at same time
Kinematics

141. Question 3 (a) decelerating uniformly and comes to rest at 4 s (b) (i)
40 m/s
(ii)
4 s
(c)
acceleration= change in speed time
acceleration= 40−0 4
acceleration = 10 m/s2
(c)
distance=area under the graph
distance= 1 2 ×40×4
distance = 80 m
Kinematics

142. KINEMATICS
LEARNING OUTCOMES
Kinematics

143. SPEED, VELOCITY & ACCELERATION
State what is meant by speed and velocity.
Calculate average speed using distance travelled/time taken.
State what is meant by uniform acceleration and calculate the value of an acceleration using change in velocity/time taken.
Discuss non-uniform acceleration.
Kinematics

144. GRAPHICAL ANALYSIS OF MOTION
Plot and interpret speed-time and distance- time graphs.
Recognise from the shape of a speed-time graph when a body is
at rest,
moving with uniform speed,
moving with uniform acceleration,
moving with non-uniform acceleration.
Calculate the area under a speed-time graph to determine the distance travelled for motion with uniform speed or uniform acceleration.
Kinematics

145. FREE-FALL
State that the acceleration of free-fall for a body near to the Earth is constant and is approximately 10 m/s2.
Describe qualitatively the motion of bodies with constant weight falling with and without air resistance (including reference to terminal velocity).
Kinematics