SafetyCâu 685 / 700
A two-leg bridle sling lifts a 4,000-pound load. Each leg makes a 30-degree angle with the horizontal. Using tension per leg = (load / number of legs) / sin(angle), what is the tension in EACH leg?
a.1,000 pounds
b.2,000 pounds
c.4,000 pounds
d.8,000 pounds
Giải thích
Correct: each leg carries half the load, 2,000 pounds vertically, but the sling is at 30 degrees from horizontal. Tension = (4,000 / 2) / sin(30 degrees) = 2,000 / 0.5 = 4,000 pounds per leg. So each leg actually carries as much as the entire load weight because of the shallow angle. 2,000 pounds ignores the angle multiplier; 1,000 pounds and 8,000 pounds do not match the calculation. This shows why shallow sling angles are dangerous.
Luyện miễn phí toàn bộ 700 câu hỏi — không cần đăng ký.
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