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PHY 101 Work, Energy and Power Objective Question
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Question

In Example 9, what is the expression derived for the coefficient of kinetic friction μ_k?
Options
A μ_k = (m₂g) / (m₁g)
B μ_k = (m₂g + ½kh) / (m₁g)
Correct Answer
C μ_k = (½kh) / (m₁g)
D μ_k = (m₂g - ½kh) / (m₁g)
Correct Answer

Option B is the correct answer.

Detailed Explanation

Applying the work-energy theorem for non-conservative forces to the system, the work done by friction (-μ_k m₁ g h) equals the change in mechanical energy (0 - m₂gh - ½kh²). Solving for μ_k yields μ_k = (m₂g + ½kh) / (m₁g).

Hint

The loss in mechanical energy (gravitational PE of m₂ and spring PE) is due to the work done by friction.

Question Info

Course: PHY 101
Topic: Work, Energy and Power
Type: Objective
Difficulty: Not specified
Question 408 of 1250
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