Determine the kinetic energy of a 1000-kg roller coaster car that is moving with a speed of 20.0m/s.

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Mass of the roller coaster = 1000 kg
Velocity of the roller coaster = 20.0 m/s
We know the formula for finding the kinetic energy is
Kinetic energy = 0.5 * mass * (velocity) ^2
                       = 0.5 * 1000 * (20)^2
                       = 0.5 * 1000 * 400
                       = 200000 Joules
So the Kinetic energy of the roller coaster is 200000 joules.
 

Yes i also think it is b