A hunter shoots an arrow at a deer running directly away from him. When the arrow leaves the bow, the deer is at a distance of 40 m. When the arrow strikes, the deer is at a distance of 50 m. The speed of the arrow is 65 m/s.
a) What must have been the speed of the deer?
b) How long did the arrow take to travel to the deer?
Toreach the dear, the arrow has to travel 50 m
so: Arrow Distance $s_a = 50$ m
Arrow Speed $v_a = 65$ m/s
b) Time to reach the dear: $t_a = \frac{s_a}{v_a}$
Distance that the dear has run $s_d = 50m - 40m$
The time the der has run is the same time the arrow flew $t_d = t_a$
The speed of the dear: $v_d = \frac{s_d}{t_d}$
sa = 50
va = 65
ta = td = sa/va
sd = 50 - 40
vd = sd / td
print(f'a) The speed of the deer is {vd:.2f} m/s.')
print(f'b) The arrow took {ta:.2f} s to reach the dear.')