That+floating+feeling

7K Forces and their effects

Describe the forces on a floating object. Explain the meaning of density. Describe two ways of measuring the volume of an object. Predict whether an object will float.
 * Objectives (what you will learn this lesson)**


 * Starter**
 * Review completed work
 * Key term quiz

> media type="file" key="ES7_Kc155_03ani.swf" width="640" height="480" > > //"If a mystery object has a weight of 10N in air and 8N in water. What is the volume of the object?"// > //Hint: remember the density of water is 1g/cm3//
 * Activities**
 * 1) Investigate up thrust for yourself using the worksheet [|Floating, sinking and density]. Calculate density and see if you can figure out why certain objects float.
 * 2) Still not sure? Learn about what upthrust is and why metal ships and air balloons float
 * 1) Look at the demonstration of upthrust. See how the weight of an object changes in water compared to air. What does this mean? Do you notice anything else happening? Discuss
 * 2) Look at upthrust in action compare the weight of objects in the air and water. Now try answering the questions on the [|Archimedes] worksheet
 * 3) Measure the volume of objects by displacement and see if it matches your calculations (height x length x width). Write a short account to explain your findings, mention Archimedes and the word "Eureka!" in your account (you may have to do some research).
 * 4) Extension: Find out about [|The Plimsoll Line], and answer the questions
 * 5) Extension: This is a hard question, see if you can work out the answer:

Review completed classwork / key term quiz
 * Summary**

Complete the gapfill on [|That floating feeling]. Either copy and complete in your exercise book or print it off when you are done.
 * Homework**