A. when it reaches the top of its flight
potential energy increases as the height of the object does, and the highest point of a ball's flight is when it reaches the top.
To find out time, you put distance over speed. So you would have to put 150 over 50. You divide 150 by 50 and you would get 3. So your answer is 3 hours.
The velocity of the ferry relative to the current is 4.5 m/s.
<h3>Relative velocity</h3>
- Relative velocity is the velocity of a body as observed from the reference point of another body either stationary or in motion.
Since the river is flowing parallel to the shore and the ferry is moving perpendicular to the shore, their velocities are at right angles to each other.
The two velocities form a right angled-triangle of sides 2, 4 and a hypotenuse which gives the relative velocity of the ferry to the current.
Using Pythagoras rule:
- Let c be the hypotenuse
- a = velocity of the ferry, and
- b = the velocity of the current, and
c² = 4² + 2²
c² = 16 + 4
c = 20
c = √20
c = 4.47 m/s
c ≈ 4.5 m/s
Therefore, the velocity of the ferry relative to the current is 4.5 m/s.
Learn more about relative velocity and Pythagoras rule at: brainly.com/question/25617868
C. Increasing the time of the force
This is because
Impulse = FΔt