9)
a)
initial velocity: V = 15 m/s
acceleration: g = 9.81 m/s^2
maximum height from throwing point = H = (V^2) / 2g = (15)^2 / (2 x
9.81) = 11.48m
b)
h = 11.48 m / 2 = 5.74 m
vf = vi + ad
vf = 15 + (9.81 x 5.74)
vf = 71.3
10)
the potential energy of a spring is 1/2 kx^2 where x is the
distance stretched or compressed from equilibrium
3.6J = 1/2 k(0.12m)^2
k = (2 x 3.6J) / (0.12m)^2
k = 500 N/m
b) not sure..
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