| Misconception |
Comment |
| The terms "energy" and "force" are interchangeable. |
The commonest example of this is the thinking of friction as energy - 'kinetic energy is transferred to friction' is a common mistake. |
| Work |
They find this hard! From the non-scientific point of view, "work" is synonymous with "labour". It is hard to convince someone that more work is probably being done dancing for one hour than studying an hour for a test.
The fact that you only 'do work' when moving against gravity or another force - so walking on the level or going down a slope is not work is hard for them to grasp. |
| An object at rest has no energy. |
They commonly associate energy of an object with its movement - they were told they had lots of energy when they ran around as young children - and when tired and still they said things like, 'I have no energy left!' |
| The only type of potential energy is gravitational. |
At one time 'potential energy' was GPE! Now we have to ensure they know of all of the types of energy that is potential because it is stored up ready to be released - potential chemical enery in fuels (not released until they are burned), potential elastic energy in a stretched spring (not released until the spring is.... |
| Gravitational potential energy depends only on the height of an object and kinetic energy only on the speed. |
 The mass and gravitational field strength often get overlooked. A circus of objects with the same GPE can be useful - as can a set of caculations of objects of equal KE - to set that up practically would be difficult! |
| Doubling the speed of a moving object doubles the kinetic energy. |
The squared factor causes many a problem! You need to work through questions on this - at GCSE stopping distances need a good grasp of this - but most want to drive - so it is a topic they actually try hard to understand! |
| Energy can be changed completely from one form to another useful (no energy losses as unwanted energy). |
Even when electricity is used in a heater there is some 'wasted' energy involved - light, sound Many think that energy is truly lost in many energy transformations because things "use up" energy. |
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