Some birds of prey, such as the northern goshawk, hunt other birds in midair. Typically, the hawk spots the prey while soaring high above, then dives in for the kill with the deadly grip of its talons. They do not shy away from larger prey, such as ducks and crows. Using the change in linear momentum, we want to estimate the impact on the hawk when completing a successful kill by clawing into the prey, which we take to be an unsuspecting American crow. Use mass of crow
mC = 455 g,
horizontal flight of the crow with speed
vC = 11 m/s,
mass of hawk
mH = 901 g,
flight path in the same plane as the crow but approaching from behind with
vH = 23 m/s
and with an angle of
θ = 74°
with the horizontal, as illustrated in the side view of the figure below.
(a) How fast does the hawk move immediately after catching the crow?
m/s
(b) By what angle has the direction of motion of the hawk changed at the impact? Note: American crows take the danger posed by high-soaring hawks very seriously. They are often seen as a group attacking the predator to drive it out of their neighbourhood.
°