Ticker Tape Motion Investigation

Aim

To investigate uniform and non-uniform motion using a ticker timer and ticker tape.

Learning Outcome

• Interpret ticker tape patterns.
• Distinguish between uniform and non-uniform motion.
• Calculate velocity.
• Calculate acceleration.
• Draw displacement-time graphs.
• Draw velocity-time graphs.
• Explain the relationship between motion graphs.

Time Allocation

Approximately 45 to 60 minutes.

How Does It Work?

A ticker timer makes dots on ticker tape at a constant frequency.

Because the intervals between individual dots are very small, learners usually measure groups of 10 dot intervals.

As the trolley moves:

• Equally spaced dots indicate constant velocity.
• Increasing spacing between dots indicates acceleration.

The ticker tape provides a visual record of the motion of the trolley over time.

Scientific Background

Displacement is the change in position of an object and is measured in metres.

Velocity is the rate of change of displacement.

Acceleration is the rate of change of velocity.

These are vector quantities because they have both magnitude and direction.

If the gaps between dots become larger, the object is accelerating.

A displacement-time graph for accelerated motion forms a curve.

A velocity-time graph for uniform acceleration forms a straight line.

An acceleration-time graph for uniform acceleration forms a horizontal line.

Hypothesis

If the trolley moves at constant velocity, then the spacing between ticker tape dots will remain constant.

If the trolley accelerates, then the spacing between the dots will increase over time.

Variables

Independent Variable

Type of motion, uniform or accelerated.

Dependent Variables

• Displacement
• Velocity
• Acceleration

Control Variables

• Same trolley
• Same ticker timer
• Same ticker tape
• Same timing frequency
• Same release method
• Same ramp length

Apparatus

• Ticker timer
• Ticker tape
• Carbon paper
• Dynamics trolley or toy car
• Inclined plane or ramp
• Metre ruler
• Stopwatch, optional
• Tape
• Graph paper
• Pencil and ruler

Safety Precautions

Experiment 1: Uniform Motion

Aim

To observe uniform motion using a ticker timer.

Method

1. Set up the ticker timer on a flat horizontal surface.
2. Thread the ticker tape through the ticker timer.
3. Attach the ticker tape to the trolley or toy car.
4. Place carbon paper in the ticker timer.
5. Switch on the ticker timer.
6. Allow the trolley to move at constant velocity across the surface.
7. Remove the ticker tape.
8. Observe the spacing between the dots.

What Learners Should Observe

• Evenly spaced dots.
• Constant spacing between intervals.
• Evidence of constant velocity.

Conclusion

Equal spacing between ticker tape dots indicates uniform motion and constant velocity.

Experiment 2: Non-Uniform Motion

Aim

To investigate accelerated motion using a ticker timer and an inclined plane.

Method

1. Set up the inclined plane at a small angle.
2. Attach ticker tape to the trolley.
3. Thread the ticker tape through the ticker timer.
4. Place carbon paper in the ticker timer.
5. Hold the trolley at the top of the ramp.
6. Switch on the ticker timer.
7. Release the trolley without pushing it.
8. Allow the trolley to move down the ramp.
9. Remove the ticker tape.
10. Observe the spacing between the dots.

What Learners Should Observe

• Increasing spacing between dots.
• Increasing velocity.
• Evidence of acceleration.

Conclusion

Increasing spacing between ticker tape dots indicates non-uniform motion and acceleration.

Measuring the Ticker Tape

Ten-Dot Interval Method

Because the spacing between individual dots is very small, learners measure 10 dot intervals at a time.

Method

1. Mark the starting point on the ticker tape as point A.
2. Count 10 dot intervals and mark point B.
3. Repeat the process to obtain points C, D, E and F.
4. Measure the total displacement from the starting point to each marked point.
5. Record the measurements in a table.

Results Table: Displacement

Point	Time (s)	Total Displacement (m)
A	0.0	0.000
B	0.2
C	0.4
D	0.6
E	0.8
F	1.0

Velocity Calculations

To calculate velocity for each interval:

1. Determine the displacement between two points.
2. Divide the displacement by the time interval, 0.2 s.

Velocity Table

Interval	Δx (m)	Δt (s)	Velocity (m.s⁻¹)	Time Midpoint (s)
A to B		0.2		0.1
B to C		0.2		0.3
C to D		0.2		0.5
D to E		0.2		0.7
E to F		0.2		0.9

Acceleration Calculations

Acceleration Table

Velocity Interval	Δv (m.s⁻¹)	Δt (s)	Acceleration (m.s⁻²)
V₁ to V₂		0.2
V₂ to V₃		0.2
V₃ to V₄		0.2
V₄ to V₅		0.2

Data Processing and Graphing

Displacement-Time Graph

• Plot time on the horizontal axis.
• Plot displacement on the vertical axis.
• Draw a smooth curve through the points.

Expected Observation

The graph should form a curve or part of a parabola because the trolley is accelerating.

Velocity-Time Graph

• Plot time on the horizontal axis.
• Plot velocity on the vertical axis.
• Draw a straight line of best fit.

Expected Observation

The graph should form a straight line because the acceleration is approximately constant.

The gradient of the velocity-time graph represents acceleration.

Acceleration-Time Graph

• Plot time on the horizontal axis.
• Plot acceleration on the vertical axis.

Expected Observation

The graph should form a nearly horizontal line because the acceleration remains approximately constant.

Graph Relationships

• The slope of a displacement-time graph gives velocity.
• The slope of a velocity-time graph gives acceleration.
• Uniform acceleration produces:
  • a curved displacement-time graph,
  • a straight-line velocity-time graph,
  • and a horizontal acceleration-time graph.

Practical Presentation

Learners may:

• cut the ticker tape into equal sections,
• paste the sections onto paper,
• and compare the spacing visually.

This helps learners observe how the spacing increases during acceleration.

Expected Results

• The ticker tape for uniform motion should show evenly spaced dots.
• The ticker tape for accelerated motion should show increasing spacing between dots.
• The velocity-time graph should form a straight line.
• The acceleration-time graph should remain approximately constant.

Questions for Learners

1. What does evenly spaced ticker tape dots indicate?
2. What does increasing spacing between dots indicate?
3. Why are ten-dot intervals used?
4. What does each dot interval represent?
5. How is velocity calculated from ticker tape data?
6. How is acceleration calculated?
7. What shape is produced by a displacement-time graph for accelerated motion?
8. What does the gradient of a velocity-time graph represent?
9. Why should a best-fit line or curve be used?
10. What could cause errors in the experiment?

Common Mistakes

• Counting dots incorrectly.
• Forgetting that the ticker timer operates at 50 Hz.
• Measuring total displacement incorrectly.
• Using inconsistent intervals.
• Drawing graphs without labels or units.
• Pulling the tape instead of allowing free motion.
• Pushing the trolley during release.
• Using damaged ticker tape.

Teacher Notes

• This experiment works well as a bridge between motion concepts and graph interpretation.
• Learners often confuse total displacement with interval displacement.
• Emphasise that acceleration can remain constant even though velocity changes.
• If the velocity-time graph does not pass through the origin, the trolley may already have had an initial velocity.
• Repeated investigations improve accuracy.

Teacher Tip

Extension Activity

Ask learners to:

• compare different ramp angles,
• compare different trolley masses,
• investigate friction using different surfaces,
• or compare ticker timer results with stopwatch measurements.

Real-World Application

Ticker tape analysis helps scientists and engineers study vehicle motion, acceleration, transport systems, crash analysis, sports science and mechanical systems.

Motion graphs are used extensively in physics and engineering.