1. Mass and Weight

16. Sorry about the wait.

17. Is she calling me fat?!!

18. Some people just don’t understand the concept of weight. Eg Which weighs more, a tonne of rocks or a tonne of soft duck feathers?

19. Some people just don’t understand the concept of weight. Eg Which weighs more, 1 tonne of rocks or 1 tonne of soft duck feathers? They both have a mass of 1 tonne.

20. Do mass and weight have the same meaning? Will 1 tonne of rocks always have the same weight? In space you can be weightless, will your mass have changed?

21. Do mass and weight have the same meaning? NO Will 1 tonne of rocks always have the same weight? In space you can be weightless, will your mass have changed?

22. Do mass and weight have the same meaning? NO Will 1 tonne of rocks always have the same weight? NO In space you can be weightless, will your mass have changed?

23. Do mass and weight have the same meaning? NO Will 1 tonne of rocks always have the same weight? NO In space you can be weightless, will your mass have changed? NO

24. Do mass and weight have the same meaning? Mass refers to the amount of ‘stuff’ in an object. This is determined by the atoms in the object. This DOES NOT change.

25. Do mass and weight have the same meaning? Weight is a force that a mass exerts. eg Masses are pulled towards the centre of the Earth by gravity. This attraction causes a mass to push against the surface of the Earth. This push is called its weight.

26. Do mass and weight have the same meaning? To better understand gravity complete the worksheets: ‘A Brief History of Gravity’ and ‘Warp Factor’.

27. Do mass and weight have the same meaning? The force of gravity causes objects to accelerate towards Earth with an acceleration of 9.8metres per second per second ie it gets faster by 9.8metres per second every second ie 9.8ms -2

28. Do mass and weight have the same meaning? This acceleration due to gravity is given the symbol g. Weight force = mass x g ie wt = mg

29. Do mass and weight have the same meaning? Eg What is my weight on Earth, if my mass is 80kg?! m = 80kg g = 9.8ms -2

30. Do mass and weight have the same meaning? Eg What is my weight on Earth, if my mass is 80kg?! m = 80kg wt = mg g = 9.8ms -2

31. Do mass and weight have the same meaning? Eg What is my weight on Earth, if my mass is 80kg?! m = 80kg wt = mg g = 9.8ms -2 wt = 80 x 9.8

32. Do mass and weight have the same meaning? Eg What is my weight on Earth, if my mass is 80kg?! m = 80kg wt = mg g = 9.8ms -2 wt = 80 x 9.8 = 784N

33. Do mass and weight have the same meaning? The size of a weight force is not constant, it can change for a mass.