UNIT: CATAPULT

ACT-Based Math: Statistical Analysis of Catapult Accuracy

OBJECTIVE:

Students analyze data from multiple launches to determine accuracy.

Materials Needed:

Catapult

Measuring tape

Target

Notebook

Student Directions:

Goal:
You will conduct multiple catapult launches toward a target, collect data on hits and misses, calculate accuracy percentages, graph your results, and analyze patterns in consistency and precision. This will help you understand how statistical analysis is used to evaluate engineering performance.

Step 1: Set Up the Testing Environment

Place a target exactly 3 meters away from the base of your catapult.

Mark the launch position clearly to ensure consistent starting conditions for each trial.

Decide how many total launches your group will complete (e.g., 20).

Step 2: Launch Projectiles and Record Data

Launch the projectile one at a time and record whether it:

Hits the target (within the outlined zone or center)

Misses the target (outside the designated target zone)

Keep a tally of each hit and miss in a data table.

Sample Data Table:

Trial Number	Hit or Miss	Distance from Center (cm)
1	Hit	12 cm
2	Miss	45 cm
…	…	…
20	Hit	5 cm

If possible, measure how far each projectile lands from the center of the target (to analyze precision, not just accuracy).

Step 3: Calculate Accuracy and Precision

Accuracy:

Precision:

Calculate the average distance from the center for all hits.

Optionally, find the range (max – min distance) or standard deviation for more advanced analysis.

Step 4: Graph Your Results

Create two graphs:

Bar graph showing hits vs. misses.

Line or scatter plot showing projectile distance from center for each trial.

Label axes clearly and title each graph (e.g., “Hit Accuracy by Trial” or “Distance from Target Center”).

Step 5: Analyze Patterns

In your notebook or worksheet, answer:

Was your catapult consistent in its launches?

Did accuracy improve with each attempt?

Are your shots clustering in a specific direction (e.g., always landing left or short)?

Do your results show more accuracy (more hits) or precision (closer groupings)?

Step 6: Group Discussion

Share and compare results with your classmates.

As a group, discuss:

"What design modifications could improve your catapult’s accuracy or consistency?"

Consider possible changes to the arm tension, base stability, angle mechanism, or projectile shape.

Optional Extension:

Try repeating the test at a different distance (e.g., 4 meters) and compare accuracy percentages.

Reflect on how distance affects consistency and launch performance.