Physics SSS2 First Term

Sub Theme: Interaction of matter, space and time

WEEK 8

Equation of forces III

Performance Objectives

Students should be able to;

1. Explain what is meant by the centre of gravity of a body.

2. Identify its position for some regular uniform bodies.

Upthrust and Archimedes principle

Content

If you try to lift up a weight in a swimming pool and then try to lift the same weight on the edge of the pool, it feels much lighter in the water.

This was supposed to have been first explained by the Greek scientist Archimedes. He said that the water gives an upward force or upthrust on any object in it.

You can weigh an object in air and then in water and actually work out the upthrust (upward force), it is the difference between the two readings..... View More