1. Measuring Mass

2. What is mass? mass – the amount of matter in an object – when you measure your weight, you are actually measuring your mass in kilograms or pounds

3. Grams and Kilograms two units are used for everyday measurements of mass – grams – the smaller unit – kilograms – the larger unit, which is equal to 1,000 grams these units are used all over the world (accept in the USA), so that when you buy a kilogram of coffee in one country, it will be the same as a kilogram of coffee in any other country

4. Then what is weight? weight – the force of gravity that pulls an object down – measured in newtons – when we say how much we “weigh”, and we give an answer in kilograms or pounds, we are actually giving our mass

5. Instruments for Measuring Mass spring balance – weighing instrument which weighs by showing the amount that an object stretches a spring

6. Instruments for Measuring Mass beam balance – weighing instrument which weighs by balancing an object against standard masses at either end of a hinged beam

7. Science Skill repeating measurements – you can make measurements more reliable by repeating them. – when you weigh an object, record the first result, remove the object from the balance and then place it back on the balance and record your new result – if there is a large difference between the results, measure again; one result must have been wrong – if the difference is small, then average the values to get the best result

8. Metric System of Units

9. Measuring Mass Exercise lets all try to measure the mass of objects

10. What you have learned Copy and complete these sentences using these key words (beam balance, gram, kilogram, mass, spring balance): The of an object is a measure of the amount of material it is made from. You can measure mass using a or a. Two units of mass are the and the.