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Q8.9: NCERT Physics - Part 2 MECHANICAL PROPERTIES OF SOLIDS 8.9 Solution: A steel cable with a radius of 1.5 cm supports a chairlift at a …

⚠️ Common Exam Traps & Conceptual Pitfalls

Students frequently insert the radius in centimetres directly into $A=\pi r^2$ and then multiply by a stress given in $\text{N/m}^2$, mixing units and inflating the load by $10^4$. Always convert the radius to metres before squaring so the area is in $\text{m}^2$.

A steel cable with a radius of 1.5 cm supports a chairlift at a ski area. If the maximum stress is not to exceed 108 N m−210^8 \text{ N m}^{-2}, what is the maximum load the cable can support?

Step-by-Step Verified Solution

**Answer:** Maximum load = 7.07×1047.07 \times 10^4 N **Step-by-Step Explanation:** Radius r=1.5r = 1.5 cm =0.015= 0.015 m. Area A=πr2=π(0.015)2=7.07×10−4A = \pi r^2 = \pi(0.015)^2 = 7.07 \times 10^{-4} m_. Maximum stress = 10810^8 N/m_. Maximum load = Stress _ Area = 108×7.07×10−4=7.07×10410^8 \times 7.07 \times 10^{-4} = 7.07 \times 10^4 N [citation:7].

All Questions in this Chapter

Q8.1 Q8.2 Q8.3 Q8.4 Q8.5 Q8.6 Q8.7 Q8.8 Q8.9 Q8.10 Q8.11 Q8.12 Q8.13 Q8.14 Q8.15 Q8.16

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