2. LI…
• Use a video camera to record motion data.
• Perform simple calculations of average
speeds.
• Plot velocity–time graphs.
• Use velocity–time graphs to calculate
distance travelled and acceleration.
3. Investigate
• We are going to use a video camera to
investigate a ball rolling down a track.
• The video camera can be used in playback
to break the motion of the ball into time
intervals.
• The track is made of two metres rulers
and so the displacement of the ball can be
recorded for each time interval.
4. Data table – use excel
time /s displacement
/m
velocity
ms-1
5. Motion Graphs – use excel
• Calculate the average velocity for your ramp
• Plot a displacement – time graph
• Estimate/calculate the gradient of the graph
near the beginning and at the end of the graph.
• Calculate the average velocity for each time
interval (use the spreadsheet)
• Plot a velocity time graph. Should be straight.
• Calculate the distance travelled using your
velocity time graph.
• Find the gradient of the velocity time graph and
hence show the acceleration.
6. Rolling Ball
• As a ball rolls down a track it
accelerates (gains speed).
• This acceleration is due to the
component of the balls weight
(caused by the acceleration of
gravity) acting down the track
g
θ
g
7. Acceleration due to gravity
• Using our results how can we find g?
• Compare your value to the accepted figure
(9.81 ms-2)
• How can we improve this investigation?
• TABOO – “get more betterer/moderner
equipment”
– reliability of the data
8. Report - homework
Rolling Ball
Aim – Use graphs and formulas to analyse the rolling of a ball and determine the
acceleration due to gravity
Variables
Diagram
Method
Results
Graphs
Discussion - Explain what the results mean by identifying trends and patterns
.Explain sources of error/uncertainty and difficulties. How these errors could be
reduced. Indicate how the experiment could be improved in future.
Conclusion
9. Friction compensate
• Try to adjust the gradient of your ramp to
make it friction compensated.
• This means the ball will not gain speed
but travel at a constant velocity.
• Check using the video camera.
• Record the data and plot a displacement
time graph.
