# Identifying the forces in a difficult circular / non-circular motion hybrid problem.

 P: 17 1. The problem statement, all variables and given/known data The problem is to create an equation to find the acceleration of the cart based upon theta. All that is given is the ball hanging is known as mass m. 2. Relevant equations $$f=ma$$ $$f=\frac{mv^{2}}{r}$$ 3. The attempt at a solution I am assuming that the car is moving to the right, since the hanging mass is tilted backwards. I am really at a loss of even just identifying all the forces exactly. What confuses me the most is that we are assuming the cart is accelerating forward, but there is no force causing it to move forward. So far, this is what I have: m being the mass, c being the cart $$F_{mx}=Tsin\theta$$ $$F_{my}=Tcos\theta - mg$$ $$F_{cx}=m_{c}a - Tsin\theta$$ $$F_{cy}=-Tcos\theta = 0$$ I know that these are probably wrong, but can someone please tell me why?