Classify the objects below based on whether they float or sink in water. Objects: Wax, Marble, Thermocol, Candle, Coin, Cork, Leaf, Eraser, Spoon, Ice-cube, Potato, Tomato, Pumpkin, Lemon
Things that float: Wax, Thermocol, Candle, Cork, Leaf, Ice-cube, Pumpkin, Lemon. Things that sink: Marble, Coin, Eraser, Spoon, Potato, Tomato. Classification is based on whether the object's density relative to water and its shape allow it to float. Objects like cork and thermocol have low density and float easily. Objects like marbles and coins are denser than water and sink. Some vegetables like pumpkin and lemon float due to their shape and air content, while potato and tomato tend to sink.
Explanation
This activity applies the concepts learned in the chapter about floating and sinking. The chapter establishes that 'Floating or sinking of an object cannot be decided based just on whether it is heavy or light. It also depends on other factors' including shape. Students are expected to predict and then test these objects. The classification helps reinforce that materials like thermocol, cork, and wax generally float, while dense materials like marble and metal objects (coins, spoons) generally sink.