Alexandra drops an egg from 30 m above the ground to hit Vanessa on the head. If Vanessa stands 3.5 meters tall. How fast is the egg moving when it strike her head? (Hint: Draw a picture and you will see why you have to consider her height and find the time first!)
This is the problem. It's worth saying that I'm working with the magnitudes and their respective scalar equations. That is, I'm not using vectors. v_e_g_g_,_i = 0m/s
g = 9.81m/s^2
h_i = 30m
h_f = 3.5m
v_e_g_g_,_f = ? t = ?
|h_f-h_i| = v_e_g_g_,_i*t + (g*t^2)/2 26.5m = 0m/s*t + ((9.81m/s^2)*(t^2))/2 t = \sqrt{2*26.5m/(9.81m/s^2)} = 2.32 s v_e_g_g_,_f = v_e_g_g_,_i + g*t v_e_g_g_,_f = 0m/s+(9.81m/s^2)*(2.32 s) v_e_g_g_,_f = 22.76 m/s
