JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2017
- Medium
- MCQ
In a physical balance working on the principle of moments, when \(5\, mg\) weight is placed on the left pan, the beam becomes horizontal. Both the empty pans of the balance are of equal mass. Which of the following statements is correct?
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) Left arm is shorter than the right arm
Step-by-step Solution
Detailed explanation
According to principle of moments when a system is stable or balance, the anticlockwise moment is equal to clockwise moment.
i.e., load \( \times \) load arm \(=\) effort \( \times \) effort arm
i.e., load \( \times \) load arm \(=\) effort \( \times \) effort arm
When \(5\, mg\) weight is placed, load arm shifts to left side, hence left arm becomes shorter than right arm
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