Energy conversion of a falling bob

AI Thread Summary
The discussion centers on the energy dynamics of a bob released from a sideways position, encountering a peg that restricts its motion. Key points include the assertion that the bob reaches its maximum speed when directly below the peg, and that it cannot return to its original height after passing the peg. The consensus is that the bob maintains the same mechanical energy throughout its motion, despite the interaction with the peg. The correct answer to the posed statements is option C, which includes statements (1) and (3). The conversation highlights the importance of understanding energy conservation in this context.
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Homework Statement



A bob is hung by a light string and and is pushed sideways. A peg of wood is placed vertically below the point of suspension of the string to hinder the motion of string as shown in the figure below: (please refer to the attachment)

The bob is released. Which of the following statements is/are correct?
(1) The bob has the largest speed when it is vertically below the peg.
(2) The bob cannot reach the original level when it is at the right side of the peg.
(3) The bob possesses same amount of mechanical energy at all time.

A (1) only
B (2) only
C (1) and (3) only
D (2) and (3) only




Homework Equations





The Attempt at a Solution



I attempted option B, but the answer is C.
For statement (1),
I thought when it is vertically below the peg, it loses some energy to the wood, so the speed is lowered.
 

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Your attachment will take a while to be approved by the mentors, but I will try to answer your question without.

Can I begin by asking you why you believe that the bob would lose some energy to the peg?
 
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