Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEET 2009
Exam
NEET
Year
2009
Subject
Physics
Chapter
Work, Power and Energy

NEET 2009 · Physics · Work, Power and Energy

A block of mass M is attached to the lower end of a vertical...

A block of mass MM is attached to the lower end of a vertical spring. The spring is hung from a ceiling and has force constant value kk. The mass is released from rest with the spring initially unstretched. The maximum extension produced in the length of the spring will be

Options

  1. AMg/kM g / k
  2. B2Mg/k2 \mathrm{Mg} / \mathrm{k}
  3. C4Mg/k4 \mathrm{Mg} / \mathrm{k}
  4. DMg/2kM g / 2 k

Correct answer

B. 2Mg/k2 \mathrm{Mg} / \mathrm{k}

Step-by-step solution

Key Idea Use the law of conservation of energy. Let xx be the extension in the spring. Applying conservation of energy mgx−12kx2=0−0⇒x=2mgk\begin{array}{ll}& \mathrm{mgx}-\frac{1}{2} \mathrm{kx}^2=0-0 \\ \Rightarrow \quad & \mathrm{x}=\frac{2 \mathrm{mg}}{\mathrm{k}} \end{array}
Practice Work, Power and Energy on Quantrex Academy →

More from Work, Power and Energy

All Work, Power and Energy questions Full Work, Power and Energy list All NEET PYQs