Question

Describe the process of floating and sinking with an example and a diagram.

Answer 1

At this level it is appropriate for students to experiment with a variety of objects to see if they float or sink in water. They should be encouraged to identify common characteristics of objects that float and those that sink. Students can try submerging a ball in a bucket of water in order to feel the upward push of the water on the ball. A more quantitative approach could involve measuring the weight of different objects to see whether that affects how they float or sink in water. Students could experiment with different sized objects with the same weight to see how this influences their floating.

Encourage students to experiment with little sealable containers such as empty film containers to see if they float, and to what level, in water. They can then experiment by putting different amounts of sand into the containers to see how the change in weight affects the level of their floating.

 Practise using and build the perceived usefulness of a scientific model or idea

The students could also model being an engineer by designing a submarine (out of a plastic drink bottle) to retrieve a sunken treasure. Introducing more sand into the bottle will increase the weight of the bottle and so increase its weight force resulting in it floating lower in the water. When the weight force is greater than the upward push of the water on the ‘submarine’ (bottle) then the ‘submarine’ will sink to recover the treasure.

 Clarify and consolidate ideas for/by the communication to others

Have students change the shape of a lump of plasticine (or ‘Blu-tack’) to see if they can make it float in water. This can lead to a discussion about why all boats don’t need to be made of wood or inflatable plastic, and a heavy metal, concrete or fibreglass ship can float on water just as successfully.

Scientists are curious and students can model being a scientist by exploring things that can affect whether an object floats such as its shape, weight or the amount or type of liquid used to float it. This investigations are a perfect opportunity for students to develop experimenting and reporting skills.

 Practise using and build the perceived usefulness of a scientific model or idea

An example of an amusing story designed to focus on the concepts of floating and sinking is ‘Who sank the boat?’ written by Pamela Allen. This story could provide opportunities for students to raise further questions about floating and sinking. 

i hope this helps you

Answer 2

, when an object will float in water it is called floating as it density is less than water but when object will sink in water it is called sinking as it density is more than water