Sinking and Floating Objects

Essential Question
What characteristics of a solid object determine whether it sinks or floats?

Objectives

 * Categorize objects whether they sink or float based on observed characteristics.
 * Interpret the results of the experiment and form new conclusions.

Introduction & Student Background
In this activity, students will use various objects to make a definition of what makes an object sink or float in water.

Materials

 * Clear container of water
 * Large cubes
 * small cubes
 * balls
 * large cylinders of aluminum
 * small cylinders of aluminum
 * clear plastic
 * milky plastic
 * wood

PREP

 * 1) Put one of each of the items in a ziploc bag.
 * 2) Fill the clear tubs with tap water.

ACTIVITY

 * 1) Give the students one of each of the objects.
 * 2) Separate the objects into a collection that would sink and a collection that would float. (2 Piles)
 * 3) Ask students what rule was used to decide how to divide these piles.
 * 4) Give the students the clear container of water. What sinks and what floats.
 * 5) Ask how does this change their definitions of what sinks and what floats.

How it fits to Standard

 * The properties of an object depend on its shape and on the material it is made from.
 * Different kinds of materials display different properties.

Follow Up
What are some household objects you could try with this? Based on your new definition, which would sink and which would float?