Final answer:
The kinetic energy of the 50 kg cart moving at a speed of 6.9 m/s is 1185.25 J.
Step-by-step explanation:
The kinetic energy of a moving object is given by the formula KE = 0.5 * mass * velocity^2. In this case, the mass of the cart is 50 kg and the speed is 6.9 m/s, so the kinetic energy is calculated as:
KE = 0.5 * 50 kg * (6.9 m/s)^2
KE = 0.5 * 50 kg * 47.61 m^2/s^2
KE = 1185.25 J
The correct answer is a) 1717.5 J.