Problem 11: An eagle is flying horizontally at a speed of 2.5 m/s when the fish
ID: 1525464 • Letter: P
Question
Problem 11: An eagle is flying horizontally at a speed of 2.5 m/s when the fish in her talons wiggles loose and falls into the lake 4.2 m below.
Part (a) Calculate the magnitude of the velocity of the fish relative to the water when it hits the water in m/s.
Numeric : A numeric value is expected and not an expression.
v = __________________________________________
Part (b) Calculate the angle, in degrees, by which the fish's velocity is directed below the horizontal when the fish hits the water.
Numeric : A numeric value is expected and not an expression.
= __________________________________________
Problem 11: An eagle is flying horizontally at a speed of 2.5 m/s when the fish in her talons wiggles loose and falls into the lake 4.2 m below.
Part (a) Calculate the magnitude of the velocity of the fish relative to the water when it hits the water in m/s.
Numeric : A numeric value is expected and not an expression.
v = __________________________________________
Part (b) Calculate the angle, in degrees, by which the fish's velocity is directed below the horizontal when the fish hits the water.
Numeric : A numeric value is expected and not an expression.
= __________________________________________
Explanation / Answer
horizontal speed of fish = 2.5 m/s
by third equation of motion
v^2 = u^2 + 2as
v^2 = 0 + 2 * 9.8 * 4.2
v = 9.073 m/s
resultant velocity = sqrt(horizontal velocity^2 + vertical velocity^2)
resultant velocity = sqrt(2.5^2 + 9.073^2)
a) resultant velocity = 9.41 m/s
angle = tan^-1(vertical velocity / horizontal velocity)
angle = tan^-1(9.073 / 2.5)
b) angle = 74.59 degree