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If a 20-kg mass has a kinetic energy of 810 Joules after falling a certain distance what is the speed of the object?
Wiki User
February 21, 2010 11:38AM
Kinetic energy
The formula for kinetic energy, Ek, could not be simpler.
Ek = (1/2)mv2, where m is mass (in kg) and v is velocity (in m s-1). If you prefer, you could write Ek = mv2/2.
or, 810j=1/2*20Kg*v2
or,v2=810j*2/20Kg
or,v=sqrt of 81
so,v=9m s-1
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