# GCSE Physics 3

 Objects with a ... Base and .... Centre of mass are there stable than those with a ..... Base and ..... Off mass Wide low narrow high The figure below shows an investigation in which a brick is titled until it topples . When the brick is pushed a little and released m it falls back to its original position (when its stable) . If the box is pushed back further , it topples . it starts to topple as soon as the centre of gravity passes over the edge of the base  explain whats happening below  A is stable as the line of action goes through the baseB is balanced because the line of action goes through the pivot C is toppled because the line of action is outside the base and pivot If the line of action of the weight of an object lies outside the base of the object There will be a turning effect and the object will topple The legs of a chair used be adults do not usually stick our beyond the seat . However babies high chairs have a much wider base explain why A object is made more stable by lowering its centre of gravity and increasing the area of its base . A high chair has to be high so will have a higher centre of gravity than a normal chair so it has a wider base to compensate for this Explain the following In terms of stability  an off road vehicle has a low centre of gravity , with wheels placed further apart bumps in the road an easily cause cars to become unstable , the fact that this car has a lower centre of gravity and large base increases its stability Explain the following In terms of stability  A desk lamp has a wide heavy base This makes the lamp more stable as the centre of gravity has been lowered and there is a large base The gravitational potential energy of anobject  depends on The height of its centre of mass above some datum level - usually ground Objects always move until Their centre of mass is at its lowest possible point , which means that as much potential energy as possible is transferred to other forms of energy Explain the stability of the objects  Cone A is clearly unstable as it is standing on its point . Note that any movement of the cone will make the position of the centre of mass lower cone a is in unstable equilibrium  cone B is stable . Any movement of of the cone will raise its centre of mass and so increase its gravitational potential energy . This means that work muse be done to change its position . Cone B is said to be in neutral equilibrium  Cone C can move , but will not topple over . Movements do not change its potential energy , it is said to be in neutral equilibrium The more work that has to be done to move an object to the point at which it will topple over , the more Stable the object is Authorghoran ID213068 Card SetGCSE Physics 3 DescriptionRevision Updated2013-04-12T14:01:21Z Show Answers