The buoyant force on a submerged block is measured along with the force applied by the block on the liquid.
Archimedes Principle, Newton’s Third Law, balanced forces.
Download video (right-click and “save link as”): Archimedes.m4v
NCEA & Science Curriculum
PHYS 1.1, PHYS 1.2 (starting point for investigations)
Setup with force plate, data logger, and data projector for a large classroom.
Lower an aluminium block into the water. The spring scale reading decreases (Archimedes Principle) and the force plate reading increases by the same amount (Newton III reaction to the buoyant force exerted by the water on the block). Aluminium is a good material to use because its density is approximately 2.7 times that of water (depending on the alloy). Steel is too dense and the spring scale reading does not change enough when the block is lowered into water.
Powerpoint and Datalogger Setup
Powerpoint (right-click and “save link as”): Arch.ppt
Contact us for the Vernier datalogger (.cmbl) file.
Be very careful with water near electronics.
Individual teachers are responsible for safety in their own classes. Even familiar demonstrations should be practised and safety-checked by individual teachers before they are used in a classroom.
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This teaching resource was developed with support from