posted by Help .
cart A with mass: 512g (0.512kg) is on a horizontal table. the cart is connected to cart b with mass: 51.0g (0.051kg) through a string that is crossing a pulley. cart A is released from rest at 60 cm(0.60m), it passes a photogate with a velocity of 0.90m/s. What is the work done by the non conservative force?