Middle School Physical Science Teacher Guide


Features 23 core lab activities that cover the fundamental concepts of Force & Motion, Energy Transfer, Electricity & Circuits, Fluids and more.

Archimedes Principle

Lab Summary

Use a force sensor to measure the change in gravitational force on an object in the air and on that same object immersed in water.


In this activity, students are introduced to Archimedes’ principle and the nature of buoyant forces. Students learn that gravity exerts a pulling force on objects that is greater in air than it is in water and investigate how the water exerts a force of its own on objects immersed in it.

Students will investigate the buoyant force of water while they:

  • Recognize that a force is a push or a pull
  • Recognize that forces have magnitudes (strengths) and directions
  • State Archimedes’ principle in their own words
  • Formulate explanations and predictions from evidence and then draw logical conclusions
  • Identify variables that can affect the outcome of an experiment; in addition, they learn to identify other variables in an experimental design that must be controlled in order to isolate the effect of one variable
  • Gain skills and confidence in using scientific measurement tools, the force sensor, as well as the graphing capability of a computer to represent and analyze data
  • Design and conduct a scientific investigation


Students gain experience conducting the following procedures:

  • Setting up the equipment and work area to measure the change in gravitational force on an object in the air and on that same object immersed in water

Sensors / Equipment Used:

PASPORT Force Sensor


Designed to measure both pulling and pushing forces. Uses range from collisions to tug-of-war.

Your Bundle Options:

Option 1:

Middle School Physical Science Bundle


Equipment bundle for teaching 23 Middle School Physical Science Teacher Guide labs.

Option 2:

Middle School Science Standard Sensor Bundle


This bundle contains the probeware needed to perform all 49 lab activities in the Middle School Science through Inquiry lab manual.

Interface Required

This experiment may require software and an interface for data collection.