physics
posted by Anonymous .
A horizontal slingshot consists of two light, identical springs (with spring constants of 37.7 N/m) and a light cup that holds a 1.37kg stone. Each spring has an equilibrium length of 50 cm. When the springs are in equilibrium, they line up vertically. Suppose that the cup containing the mass is pulled to x = 0.7 m to the left of the vertical and then released.

Is there a question here?

(a) Stretch in the spring is
L₁=sqrt(x²+L₀²) = sqrt(0.7² +0.5²)=0.86 m
Elongation is
Δx= L₁L₀= 0.860.5=0.36 m.
E(total) = PE=2•k•Δx²/2=2•37.7•0.36²/2=4.9 J.
(b) PE=KE =mv²/2
v=sqrt(2•PE/m) = sqrt(2•4.9/1.37) = 2.67 m/s 
A horizontal slingshot consists of two light, identical springs (with spring constants of 45.7 N/m) and a light cup that holds a 1.37kg stone. Each spring has an equilibrium length of 50 cm. When the springs are in equilibrium, they line up vertically. Suppose that the cup containing the mass is pulled to x = 0.7 m to the left of the vertical and then released. Determine
a) the system’s total mechanical energy.
Tries 0/4
b) the speed of the stone at x = 0.