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− | [[Image:Energy%20for%20KOER_html_m7d349003.png]]Notice | + | [[Image:Energy%20for%20KOER_html_m7d349003.png]]<br>Notice |
| that the work done is the same in all the three cases above though | | that the work done is the same in all the three cases above though |
| the force applied is different. Greater the angle of inclination, | | the force applied is different. Greater the angle of inclination, |
| greater is the force needed. | | greater is the force needed. |
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| Thus W = F x d if the distance travelled d is in | | Thus W = F x d if the distance travelled d is in |
| the same direction as the force. If the direction in which the object | | the same direction as the force. If the direction in which the object |
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− | [[Image:Energy%20for%20KOER_html_6f7bb14c.gif]]If | + | [[Image:Energy%20for%20KOER_html_6f7bb14c.gif]]<br>If |
| the force is acting perpendicular to the direction of the work done, | | the force is acting perpendicular to the direction of the work done, |
| there is no work done. If you are carrying a heavy bag in your hand | | there is no work done. If you are carrying a heavy bag in your hand |
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| for the bag. | | for the bag. |
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| Work done, is defined as a particular form of | | Work done, is defined as a particular form of |
| product of two vectors – force and displacement. Such a product is | | product of two vectors – force and displacement. Such a product is |
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| the context of work done, this is easy to understand. You don’t do | | the context of work done, this is easy to understand. You don’t do |
| work in a particular direction – you just do work. | | work in a particular direction – you just do work. |
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| The unit of work done is joules. 1 J of work is | | The unit of work done is joules. 1 J of work is |
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| The rate of doing work is defined as the power. Power is defined as | | The rate of doing work is defined as the power. Power is defined as |
| (work done)/ time taken. | | (work done)/ time taken. |
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| Power = work done/ time = force x displacement/ | | Power = work done/ time = force x displacement/ |
| time = force x velocity | | time = force x velocity |
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| Its unit is Watt. | | Its unit is Watt. |
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| === Energy, types of energy-Kinetic and potential === | | === Energy, types of energy-Kinetic and potential === |
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