You started to decelerate the ball (i.e. ball became in contact with your hands)

Question

You started to decelerate the ball (i.e. ball became in contact with your hands) when it was am above ground, and ball come to a complete stop (velocity = 0)when it was 0.6 m above ground. What was the potential, kinetic, and total mechanical energy of the ball when it come to a stop? (Height = 0.6 m, velocity = 0 m/s) e) How much work did you do on the ball to bring it to a stop? f) What was the average force you exerted on the ball to bring K to a stop? g) In a few complete sentences, describe how the potential, kinetic, and total mechanical energy of the ball changed when it was free-falling from 15m to 1m. h) In the complete sentence, describe how the potential, kinetic, and total mechanical energy of the ball change from the time you made contact with the ball to the time the ball came to a complete stop." 20664891,Prove that

Explanation / Answer

Part d

P.E. of ball at the point where it came to stop = mgh =0.6mg

K.E. of ball at point where come to stop=0

Total mechanical energy at the point where it came to stop= P.E. + K.E.=0.6mg

Part e

K.E. at 15 m, K15 = 0

K.E. at 1 m, K1 = change in P.E. = 14mg

Hence work done on ball=14mg + 0.4mg = 14.4 mg

Part f

Average force on ball=work done/displacement=14.4mg/0.6 = 24 mg N

Part g

Initially P.E. = 15mg

K.E. = 0

Total mechanical energy = 15mg

Then, as ball starts falling down, P.E. changes into work which finally changes to K.E. And when it reaches 1m then

P.E. = mg

K.E. = 14 mg

Total mechanical energy = 15mg

Part g

Initially P.E. = mg

K.E. = 14mg

Total mechanical energy = 15mg

Then, as ball is caught in hands, work is being done against the motion of the ball and as it reaches 0.6m then

P.E. = 0.6mg

K.E. = 0

Total mechanical energy = 0.6mg

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.