The car has 200 J of KE at point C and is at the lowest point why is the total ME at point D
The total mechanical energy (ME) at point D is equal to the sum of the kinetic energy (KE) and potential energy (PE) at that point. Since the car is at the lowest point (typically the point of reference for potential energy calculations), the potential energy at point D is zero, as there is no height or gravitational potential energy present at this point.
Therefore, the total mechanical energy at point D is equal to the kinetic energy at that point, which is given as 200 J.