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⁻², what is the maximum load the cable can support?
The maximum load the cable can support is approximately ⁴ N (or about 70.7 kN).
Explanation
This question tests the understanding of the relationship between stress, force, and cross-sectional area. The formula Stress = Force/Area is used. Given the maximum permissible stress and the radius of the cable, we first calculate the cross-sectional area, then rearrange the formula to find the maximum force (load) the cable can withstand.
Solution Steps
Step 1: Convert radius to SI units. Radius r = 1.5 cm = ⁻² m
Step 2: Calculate the cross-sectional area of the cable. A = πr² = 3.14 × (⁻²)² = × 10⁻⁴ = ⁻⁴ m²
Step 3: Apply the stress formula. Stress = Force/Area, therefore Force = Stress × Area
Step 4: Calculate maximum load. F = 10⁸ N m⁻² × ⁻⁴ m² = ⁴ N ⁴ N