PartA An eagle\'s dive. When diving for prey, bald eagles can reach speeds of 20
ID: 2041043 • Letter: P
Question
PartA An eagle's dive. When diving for prey, bald eagles can reach speeds of 200 mph (322 km/h). Suppose a 4.5 kg eagle flying horizontally at 322 km/h suddenly grasps and holds a stationary 3.0 kg jackrabbit in her talons What's the eagle's speed just after grasping the rabbit? Express your answer to two significant figures and include the appropriate units. Value Units Submit Part B What percent of her kinetic energy is lost during the process? Express your answer using two significant figures. Submit Request AnswerExplanation / Answer
mass of eagle m1 = 4.5 kg mass of rabbit m2 = 3 kg
intial speed
v1i = 322 km/h = 322*(5/18) = 89.4 m/s v2i = 0
initial momentum Pi = m1*v1i + m2*v2i
after grasping
fial speed v1f = v2f = v = ?
final momentum Pf = (m1 + m2)*v
from momentum conservation
Pf = Pi
(4.5 + 3)*v = (4.5*89.4) + 0
v = 53.6 m/s
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part B
initial kinetic energy Ki = (1/2)*m1*v1i^2 = (1/2)*4.5*89.4^2 = 17983 J
final kinetic energy Kf = (1/2)*(m1+m2)*v^2 = (1/2)*7.5*53.6^2 = 10774 J
energy lost dE = Kf - Ki = -7209 J
%of energy lost = dE/E = 7209/17983)*100 = 40 %
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part(C)
if v2i = -2 m/s
(4 + 3)*v = (4.5*89.4) - (3*2)
v = 52.84 m/s
DONE please check the answer. any doubts post in comment box