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Teacher’s Notes. A slide contains teacher’s notes wherever this icon is displayed - To access these notes go to ‘Notes Page View’ (PowerPoint 97) or ‘Normal View’ (PowerPoint 2000). Notes Page View. Normal View. Flash Files.
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Teacher’s Notes A slide contains teacher’s notes wherever this icon is displayed - To access these notes go to ‘Notes Page View’ (PowerPoint 97) or ‘Normal View’ (PowerPoint 2000). Notes Page View Normal View Flash Files A flash file has been embedded into the PowerPoint slide wherever this icon is displayed – These files are not editable.
Weight and Mass Weight and mass are not the same. Mass is the amount of matter in an object. This will have the same value anywhere in the Universe including space. Weight is a force and it is caused by the pull of gravity. In fact, weight is the pull of gravity acting on a mass.
Weight and Mass Weight is a force so is measured in Newtons. Like other forces it has both magnitude and direction. Mass is not a force, it is measured in kilograms. A 1 kg mass will weigh less on the moon than it does on Earth. This is because the force of gravity is less on the moon because the moon is smaller than the Earth. An astronaut could jump 20 feet into the air on the moon because gravity is less. However, he still has the same body, and the same mass, it just weighs less, because he is on the moon and gravity is weaker.
Weight and Mass So, a scientist should NEVER say “He weighs 50kgs” but, should say “He has a mass of 50kgs”, or the scientist could say: “the gravitational force acting on his mass is about 500 Newtons”. This is the same as saying: “his weight is about 500 Newtons”.
Gravity Gravity is an attractive force that acts between all masses. The force depends on the mass of the object. All objects produce a gravitational force but it is only significant when the mass is about the size of a moon or planet. Think about it: When you jump the gravitation force of the Earth pulls you down. Your gravitation force pulls the Earth up!
Space shuttle - smaller mass Force of gravity The force of gravity depends on the mass of the planet and how close you are to it. Objects will have higher weight on Jupiter because it has a larger mass than Earth. Earth - large mass
The Solar System The planets orbit the Sun (not drawn to scale) because it has a massive gravitational pull. Notice that the orbits are all ALMOST circular. The shape is called an ellipse. We are still finding out more about the Solar System.