The kinetic energy is calculated as KE=1/2 MV squared
Where M is the mass and V is the velocity solving form we get 2KE =MV squared
M=2KE over/ V squared
Now we can replace the kinetic energy KE=500J and the velocity V=15m/s
To get m=2(500) over / 15 to the second
=1000/225 =4.44kg mass of the soccer ball is 4.44 kg
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