A pelican flying along a horizontal path drops
a fish from a height of 4.7 m. The fish travels
8.5 m horizontally before it hits the water
below.
What was the pelican’s initial speed? The
acceleration of gravity is 9.81 m/s2 .
Answer in units of m/s
To find the pelican's initial speed, we can use the equations of motion. We'll start by determining the time it takes for the fish to fall.
The first step is to set up an equation using the vertical motion equation:
h = (1/2) * g * t^2
Where:
h = height (4.7 m)
g = acceleration due to gravity (9.81 m/s^2)
t = time
Rearranging the equation to solve for time:
t^2 = (2h) / g
t = sqrt((2 * 4.7) / 9.81)
t ≈ 0.966 seconds
Now that we have the time it takes for the fish to fall, we can use it to calculate the horizontal distance the pelican traveled:
d = v * t
Where:
d = horizontal distance (8.5 m)
v = pelican's initial speed
Rearranging the equation to solve for velocity:
v = d / t
v = 8.5 / 0.966
v ≈ 8.79 m/s
Therefore, the pelican's initial speed was approximately 8.79 m/s.