# Changes

,  15:49, 4 December 2013
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===Notes for teachers===

===Notes for teachers===

''These are short notes that the teacher wants to share about the concept, any locally relevant information, specific instructions on what kind of methodology used and common misconceptions/mistakes.''

''These are short notes that the teacher wants to share about the concept, any locally relevant information, specific instructions on what kind of methodology used and common misconceptions/mistakes.''
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'''How do we perceive this weight?'''
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When you stand on a surface, the force of the Earth's gravity is acting upon you downwards and there is a normal force exerted by the surface on which you stand. Since you stand on a firm surface and there is no acceleration, the normal force is equal to the gravitational force and this is equal to mg. If an object is suspended from a spring, the gravitational force will be balanced by the tension force in the string.
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Weight is that supporting force felt by an object in equilibrium; this opposes and balances the gravitational pull of the Earth. Thus, humans experience their own body weight as a result of this supporting force, which results in a normal force applied to a person by the surface of a supporting object, on which the person is standing or sitting. In the absence of this force, a person would be in free-fall, and would experience weightlessness. It is the transmission of this reaction force through the human body, and the resultant compression and tension of the body's tissues, that results in the sensation of weight.
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When an object is in equilibrium, it only experiences the gravitational and restoring force/ Weight is mass multiplied by the acceleration due t gravity
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===Activity No # ===

===Activity No # ===

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{| style="height:10px; float:right; align:center;"