Assessing Linear Motion in Sports and Exercise Activities
Aim
To investigate the linear motion of sports and exercise activities, primarily different types of
sprinters, to explore which areas they could improve on.
Introduction
Linear motion is when an object “moves along a straight line in a particular direction”,
(Linear Motion, 2020). This can be used to identify different factors within running: speed,
velocity, acceleration, deceleration and momentum.
Speed is the “distance traveled per unit of time”, (What Speed Actually Means in Physics,
2020). It’s used to figure out how fast an object is moving. Similarly, velocity is “the speed at
which something moves”, (What Is Velocity in Physics, 2019), however this is in “one
direction”. According to Newton’s first law of motion, objects that do not experience any net
force will continue to move in a straight line with a constant velocity until they are subjected
to a net force. A net force is simply a “sum of all the forces that act upon an object”
(Determining the Net Force).
Acceleration is caused by either a “change in magnitude or the direction of the velocity”
(Acceleration, no date) and can be defined as the “rate of change in speed (or velocity)”
(BBC Bitesize Acceleration, no date). Deceleration is “an acceleration with a direction
opposite to that of the velocity” (Acceleration, no date).
Finally, momentum is interpreted as “the strength or force that something has when it is
moving” and is due to the moving object’s mass and motion, (Momentum, no date). Mass
and weight are slightly different in that mass is a “measure of the amount of matter in an
object” (Definition of Mass, no date). However, weight is “another word for the force of
gravity”, (What is Weight?, no date).
Methodology
The sprinters’ results were documented by an external source during competition and
training, so were used as secondary data. With this data, linear motion equations were able
to be calculated. A document of four different track athletes’ times was given as the data that
would be used in this investigation, showing competition versus training times, two of which
will be used in this report.
Four types of calculations were made based on each athlete’s data: speed, velocity,
acceleration / deceleration, and momentum. In addition to these, the distance and
displacement was also calculated. Distance refers to how “how much ground an object has
covered during its motion” whereas displacement is “how far out an object is” / “the object’s
overall change in position”, (Distance versus Displacement, no date).The two athletes
chosen for this were olympic champions Usain Bolt (100m) and Wayde van Niekerk (400m).
Results
Table 1.1 - Usain Bolt 100m Competition Results
Dist (m) 0-10 10-2 20-30 30-4 40-50 50-60 60-70 70-80 80-90 90-100
0 0
Time (s) 1.85 1.02 0.91 0.87 0.85 0.82 0.82 0.82 0.83 0.90
Speed 5.41 9.80 10.99 11.49 11.76 12.20 12.20 12.20 12.05 11.11
, Velocity 10.32 10.32 10.32 10.32 10.32 10.32 10.32 10.32 10.32 10.32
Acceleration 2.92 9.61 12.08 13.21 13.84 18.87 14.47 14.87 14.52 12.34
Momentum 970.1 970.1 970.1 970.1 970.1 970.1 970.1 970.1 970.1 970.1
100m Time 9.69s
Table 1.2 - Usain Bolt 100m Training Results
Dist 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 90-100 100m
(m)
Drill Time
No. (s)
1 1.92 1.21 1.04 0.99 0.92 0.91 0.92 0.92 0.94 0.96 10.73
2 1.89 1.17 1.01 0.97 0.90 0.89 0.88 0.89 0.91 0.94 10.45
Speed 5.25 8.41 9.76 10.21 10.99 11.11 11.12 11.05 10.81 10.53
Velocity 9.44 9.44 9.44 9.44 9.44 9.44 9.44 9.44 9.44 9.44
Acceleration 4.97 7.93 9.25 9.63 10.37 10.49 10.37 10.37 10.15 9.93
Momentum 660.8 660.8 660.8 660.8 660.8 660.8 660.8 660.8 660.8 660.8
Table 2.1 - Wayde van Niekerk 400m Competition Results
Dist (m) 0-100 100-200 200-300 300-400
Time (s) 10.69 9.93 10.66 11.75
Speed 9.36 10.1 9.38 8.51
Velocity 9.36 20.14 28.14 34.
Acceleration 0.88 1.01 0.88 0.
Momentum 655.2 1,409.8 1,969.8 2,
400m Time 43.03s
Table 2.2 - Wayde van Niekerk 400m Training Results
Dist (m) 0-100 100-200 200-300 300-400 400m