When the ball starts its motion from the ground, its potential energy is zero, so all its mechanical energy is kinetic energy of the motion:
where m is the ball's mass and v its initial velocity, 20 m/s.
When the ball reaches its maximum height, h, its velocity is zero, so its mechanical energy is just gravitational potential energy:
for the law of conservation of energy, the initial mechanical energy must be equal to the final mechanical energy, so we have
From which we find the maximum height of the ball:
Therefore, the answer is
yes, the ball will reach the top of the tree.
Answer:
<u>1.8kJ</u>
Explanation:
Formula :
<u>Energy used = Power x time</u>
<u />
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Given :
⇒ Power = 30 W
⇒ Time = 1 minute = 60 seconds
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Solving :
⇒ Energy used = 30 W × 60 s
⇒ Energy used = 1,800 J
⇒ Energy used = <u>1.8kJ</u>
That they travel in a vacuum. All other waves require a medium in which they wave.
Burning of paper is the answer