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Work and Kinetic Energy
Why are they clapping he did not do work
K.E is a scalar QuantityK.E Can not be NegativeK.E is measured by Joule (J)
Work
Work is energy transferred to or froman object by means of force acting
on the object
Work is said to be positive if transferred tothe object and negative if transferred from
the objectWork is a scalar quantity that has the same
units of Energy ( Joule )
What is work ?
What is the difference between work and doing work ? And what are theunits of work ?.
I applied the breaks to stop the carwhat work did friction do on my
car ?
Answer
Can we replace the forces bytheir resultant ?Then work is defined as:And work K.E theorem becomes
=10N
=12N
What is the work done by mg and N ?
Moving Down
Moving up
If it starts from rest and ends at restor if it moves with constant velocity then
Sample Problem
As the box is stationary at the the start and the end of the motion
Sample Problem
Alternative way