Answer: 15 kg
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Work Shown:
KE = 480
v = 8
KE = (1/2)*m*v^2
480 = 0.5*m*8^2
480 = 0.5*m*64
480 = 0.5*64m
480 = 32m
32m = 480
m = 480/32
m = 15
The SI unit for mass is in kilograms
Also a joule is defined with kilograms since 1 J = 1 kg*m/s^2
1 joule is the amount of energy needed to move an object of mass 1 kg with an acceleration of 1 m/s^2
So this is why the mass m is in kilograms.
