Hi, i'm new here. I have a problem. 1. The problem statement, all variables and given/known data A box has the mass m, held by two horizontal ropes and two vertical ropes. The box is inside a still car. If the car accelerated suddenly with the accekeration of a then the box will remain still inside the car. What is : a. The acceleration of the box/car? (state it in t1, t2, t3, t4 and g) b. The separation after the time t? (state it in t1, t2, t3, t4, t and g) The illustration is here -> xttp://i31.tinypic.com/izvnev.jpg (change x to h) 2. Relevant equations [tex]\Sigma F = ma[/tex] 3. The attempt at a solution a. t3 + t1 = ma m = (t3 + t1)/a (1) t4 + t2 = mg m = (t4 + t2)/g (2) (t3 + t1)/a = (t4 + t2)/g a = g(t3 + t1)/ t4 + t2 (3) b. S = Vt S = a * t * t S = (g(t3 + t1)/ t4 + t2) * t^2 S = g (t^2) ((t3 + t1)/(t4 + t2)) I actually don't really know how the tensions work. I hope someone can explain it to me. And sorry, i'm not used to using latex yet.