<span>As it is uniform circular motion therefore speed is constant. Therefore we can rule out option B. Also in circular motion the direction of velocity vector changes therefore velocity can't be constant. Therefore option B is incorrect as well. Also centripetal acceleration is always towards the center so option D is wrong as well.
That implies
option A is correct.</span>
Answer:
13 km
Explanation:
The bird flies from the runner, to the finish line, and back to the runner. We can write two equations for the distance it travels:
d = 7.8 km + 7.8 km − 4.9 km/hr × t
d = 24.5 km/hr × t
Solve for t in the second equation and substitute into the first:
t = d / 24.5
d = 7.8 + 7.8 − 4.9 (d / 24.5)
d = 15.6 − 0.2 d
1.2 d = 15.6
d = 13
The bird flies a cumulative distance of 13 km.