An Australian emu is running due north in a straight line at a speed of 13.0m/s and slow down to a speed pf 9.50 m/s in 4.70s. (a) what is the magnitude and direction of the birds acceleration? (b) Assuming that the acceleration remains the same, what is the bird’s velocity after an additional 1.70s has elapsed?
(a) To find the magnitude of the bird's acceleration, we can use the equation:
acceleration = (final velocity - initial velocity) / time
acceleration = (9.50 m/s - 13.0 m/s) / 4.70 s
acceleration = -3.50 m/s / 4.70 s
acceleration ≈ -0.745 m/s²
Since the bird is slowing down, the acceleration is negative.
The direction of the bird's acceleration is opposite to its velocity, so it is due south.
(b) Using the same acceleration as before, we can find the bird's velocity after an additional 1.70s using the equation:
final velocity = initial velocity + (acceleration * time)
initial velocity = 9.50 m/s (from part a)
acceleration = -0.745 m/s² (from part a)
time = 1.70 s
final velocity = 9.50 m/s + (-0.745 m/s² * 1.70 s)
final velocity = 9.50 m/s - 1.267 m/s
final velocity ≈ 8.233 m/s
The bird's velocity after an additional 1.70s is approximately 8.233 m/s.