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Inclined Plane Cri C

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Inclined Plane Experiment Criterion C
Name: Connie Chen
Class: Grade 9B
Date: Nov, 8th, 2019
Qualitative Data:
The aim of this experiment is to investigate and determine how can different inclination angles
of a tilted ramp affect the velocity/acceleration of a marble rolling down from the inclined plane. The
angles of inclination of a ramp are switched from shallow to wide when three trials of the experiment
are completed. Furthermore, the ramp with a total length of 4.8m was also separated into four
identical portions: 1.2m, 2.4m, 3.6m and 4.8m. Each portion was marked with a sign to make it
clearer for students to calculate the change of velocities after stopping a timer from running
whenever the marble went pass a sign. Both the velocities and the accelerations are calculated from
the time taken recordings for a marble to roll down a ramp with two types of inclinations. Eventually,
the final result of this experiment was concluded by comparing the different calculations of the two
inclination angles of the ramp.
According to the observations during the experiment, the marble seemed like rolling down faster
on the plane when it had a wider angle of inclination. On the contrary, only seen by naked eyes, the
speed of the marble didn’t look like it was changing when the marble was rolling down from a
shallow angle. Also, while using a book at the end of the ramp to resist the marble from keep on
running, the force that the marble generated of bumping into the book seemed to be greater when the
marble was rolling down from a wider angle of inclination.
Data Collection:
Table 1: Raw data of the time taken recordings (s) a marble rolled down from a tilted ramp with two
types of inclination angles (degreeº) and four portions of lengths/distance markings (m).
The table below shows the raw data of the time taken for a marble to roll down from a tilted
plane with two types of inclination angles: shallow and wide. Four distance markings (1.2m, 2.4m,
3.6m and 4.8m), with students standing by and recording with timers, are labeled with ruler on the
plane to clarify the time taken for the marble to go pass each of them. Three trials are completed for
each of the inclination of the ramp to ensure the reliability of the experiment.
Distance
markings
(meters)
1.2
2.4
3.6
4.8
Timers
Timer 1
Timer 2
Timer 3
Timer 4
Angles of Inclination (Degreeº)
Shallow Angle
Wide Angle
Trial 1 (s) Trial 2 (s) Trail 3 (s) Trial 1 (s) Trial 2 (s)
1.65
2.85
2.66
1.50
1.72
2.75
4.08
4.16
2.47
2.53
3.58
4.95
4.43
2.71
3.14
4.50
5.93
5.91
3.94
4.00
Trial 3 (s)
1.78
2.53
3.08
3.94
Data Processing:
1) The average recordings of the time taken for a marble to roll down an inclined plane will be
calculated at four distance markings for two types of inclination angles (shallow and wide).
Formula: Average time taken recordings at each distance marking (s) = The sum of time taken for
three trials of experiment in the same inclination angle (s) / Number of trials (three)
Sample calculation for the average time taken recordings for all three trials with the shallow
inclination at the distance of 2.4m:
(2.75s + 4.08s + 4.16s) / 3 = 3.66s (approximately)
2) The average velocities of a marble rolling down an inclined plane will be calculated for two
types of inclination angles and at four distance markings.
Formula: Average velocity calculations for each inclination and distance marking (m/s) = The
overall distance of the marble rolling down (m) / Time taken (s)
Sample calculation for the average velocity when the marble is at 1.2m from the plane with a wide
inclination:
1.2m / 1.67s = 0.72 m/s (approximately)
3) The average accelerations of a marble rolling down the tilted ramp is calculated for two angles of
inclination and four distance markings.
Formula: Average acceleration of a marble rolling down (m/s²) = Δ Velocity (Final velocity – Initial
Velocity) (m/s) / Time taken (s)
Sample calculation for the acceleration of the marble at 1.2m of the ramp with a shallow inclination
angle:
0.50m/s / 2.39s = 0.21m/s²
Data Presentation:
Table 2, Graph 1: The average calculations of the time taken (s) a marble is required to roll down an
inclined plane with shallow and wide inclinations (degreeº) and the four distance markings (m).
The table and the graph below are showing the average time taken recordings (s) a marble rolled
down from a tilted ramp with two inclinations. The time taken was affected by shallow and wide
inclination angles, and was recorded at four distance markings: 1.2m, 2.4m, 3.6m and 4.8m.
Distance markings
(meters)
1.2
2.4
3.6
4.8
Average of the Time Recordings for Different Angles of Inclination (s)
Shallow Angle (s)
Wide Angle (s)
2.39
1.67
3.66
2.51
4.32
2.98
5.45
3.96
Average Time Taken for the Marble to Roll Down
Time Taken (s)
6
5
4
3
2
1
0
Marking 1
Marking 2
Marking 3
Marking 4
Distance Markings (m)
Average of the Time Recordings for Different Angles of Inclination (s) Shallow Angle
(s)
Average of the Time Recordings for Different Angles of Inclination (s) Wider Angle (s)
Table 3, Graph 2: The average velocities (m/s) of the marble rolling down from an inclined plane at
four distance markings (m) and two distinctive angles (degreeº).
The table and the graph below both show the average velocities (m/s) calculated from the
average time taken recordings (s) at shallow and wide angles of inclination the ramp has. The
velocities are calculated when each timer was stopped at each distance marking (1.2m, 2.4m, 3.6m
and 4.8m). The table and the graph are using the second formula in data presentation.
Distance markings
(meters)
1.2
2.4
3.6
4.8
The Calculated Average Velocities of the Marble Rolling Down (m/s)
Shallow Angle (m/s)
Wide Angle (m/s)
0.50
0.72
0.66
0.96
0.83
1.21
0.88
1.21
Average Velocities of the Marble Rolling Down
1,4
Velocity (m/s)
1,2
1
0,8
0,6
0,4
0,2
0
Marking 1
Marking 2
Marking 3
Marking 4
Distance markings (m)
Average Velocity of the Marble Rolling Down (m/s) Shallow Angle (m/s)
Average Velocity of the Marble Rolling Down (m/s) Wide Angle (m/s)
Table 4, Graph 3: The average accelerations (m/s²) of the marble rolling down from a tilted plane
with two angles of inclination (degreeº) and at four identical distance portions.
Acceleration is known as the rate in which an object is changing its velocity. The table and the
graph below are both showing the average accelerations of a marble rolling down from an tilted
plane that varies between shallow and wide angles of inclination (degreeº). Each acceleration is
calculated at a distance marking on the ramp. Also, the accelerations being calculated below are
based on the change in velocities in table 3 and graph 2, using the third formula in data presentation.
Distance markings
(meters)
1.2
2.4
3.6
4.8
0.21
0.18
0.19
0.16
Calculated Accelerations based on Average Velocities (m/s²)
Shallow Angle (m/s²)
Wide Angle (m/s²)
0.43
0.38
0.41
0.72
Calculated Accelerations Based on Average
Velocities
Acceleration (m/s²)
0,8
0,7
0,6
0,5
0,4
0,3
0,2
0,1
0
Marking 1
Marking 2
Marking 3
Marking 4
Distance Markings (m)
Calculated Accelerations based on Average Velocities (m/s²) Shallow Angle (m/s²)
Calculated Accelerations based on Average Velocities (m/s²) Wide Angle (m/s²)
Conclusion and Evaluation:
The goal of this experiment was to investigate and determine how the two inclination angles
(shallow and wide) of a ramp may affect the velocity and the acceleration of a marble rolling down
the ramp. As shown in Table 2 and Graph 1, by observing the two lines, it is obvious that the slope of
the line representing the shallow angle is steeper than the slope of the line representing the wide
angle. Also, the line of the shallow angle is distinctly higher than the wide angle, which means that it
took much more time for the marble to roll down the shallow angle. According to Table 3 Graph 2
and Table 4 Graph 3, the velocities and the accelerations of the marble rolling down the wider angle
is obviously greater than the marble does on the shallow angle, the red lines have higher and steeper
lines than the blue lines on the graphs. Especially when the red lines are approaching to the end, the
slope of the acceleration line surges in a great amount at marking 4s. The data suggests that the
inclination of ramps does affect the velocities and accelerations of a marble rolling down. The results
of the experiment are likely due to the approaches of the marble to free-fall. When the ramp gets
steeper and has a larger inclination angle, the marble rolling down will have a greater gravitational
acceleration energy and a larger inertia to push it down the ramp. The acceleration of the marble is
accumulating and therefore causing the velocity to enlarge while the it is rolling down. The result of
the experiment supports the hypothesis made. This is because the ramp that has a wider inclination
angle has greater accelerations and velocities than the ramp with a shallow angle.
Evaluation and Improvements:
Weakness/Source of Error
Possible effect on data and
magnitude of weakness/error
Independent Variable: The inclinations of the ramp.
During the experiment, it
This won’t affect the actual
wasn’t ensured that the ramp
result widely, since it was
was staying at the exact same
ensured that the inclinations of
position all the time. The ramp ramp were keeping the same
moved slightly and might
for each three trials of the
Suggested Improvements
To ensure that the ramp won’t
be removed when it is in the
same inclination angle,
students doing the experiment
should be careful and make
experiment. The only factor
sure that they won’t kick the
being slightly shifted was the
ramp accidently.
position the ramp.
Dependent Variable: The accelerations and velocities of the marble.
The marble wasn’t pushed
Giving an extra force to the
To avoid pushing the marble
down the ramp with the exact
marble will generate more
when it is on top of the tilted
same force during the
energy to the marble rolling
plane, the student dropping it
experiment. It would probably down the ramp. The marble
should make sure that he/she
cause an effect on the velocity might have a greater velocity
isn’t bringing extra forces. The
and the acceleration of the
or gravitational acceleration
student should only release the
marble.
energy while rolling down the ball during the experiment.
inclined plane.
Controlled Variable: The time the students at each distance marking start their timers.
During the experiment, the
If some students started their
To avoid this from happening,
time that the students at each
timers before the marble
the person releasing the marble
distance marking start their
released, and others started
could give a signal to others
timers are not controlled
after the marble started rolling who are starting their timers. In
accurately. If students were not down, the recordings of the
this way, everyone could start
starting their timer at the same time taken of marbles won’t be their timers almost the same
time, it will probably cause
accurate enough.
time.
effects on the calculations and
the final results of the marble’s
velocities.
cause effects on the final
results.
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