Question:
A uniform rod of mass 250 g having length 100 cm is balanced on a sharp edge at the 40 cm mark. A mass of 400 g is suspended at the 10 cm mark. To maintain the balance of the rod, the mass to be suspended at the 90 cm mark is:
A uniform rod of mass 250 g having length 100 cm is balanced on a sharp edge at the 40 cm mark. A mass of 400 g is suspended at the 10 cm mark. To maintain the balance of the rod, the mass to be suspended at the 90 cm mark is:
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In torque problems, always use the equation \( \tau_{{Net}} = 0 \) and set up the moments about a point to solve for unknowns.
Updated On: Mar 17, 2025
- 300 g
- 200 g
- 290 g
- 190 g
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The Correct Option is D
Solution and Explanation
The equation for torque balance is:
\[
\tau_{{Net}} = 0 \quad \Rightarrow \quad (400g \times 30) = (250g \times 10) + (mg \times 50)
\]
Solving for \( m \), we get:
\[
m = \frac{12000 - 2500}{50} = 190 \, {g}
\]
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