physics
posted by monic on .
A 52kg pole vaulter running at 12 m/s vaults over the bar. Her speed when she is above the bar is 0.7 m/s. Neglect air resistance, as well as any energy absorbed by the pole, and determine her altitude as she crosses the bar.

hmax = (V^2Vo^2)/2g.
hmax = 0144/19.6 = 7.35 m.
V = Vo + gt.
t = (VVo)/g = (0.70)/9.8 = 0.0714 s.
h = ho  0.5g*t^2'
h = 7.35  4.9*(0.0714)^2 = 7.325 m. =
her Alt. 
If an automobile engine delivers 48.2 hp of power, how much time will it take for the engine to do 6.80 ✕ 105 J of work? (Hint: Note that one horsepower, 1 hp, is equal to 746 watts.)