Soru

Zorluk: OrtaWheel and Axle

Sailors are using a manual capstan to pull an anchor chain. The capstan drum, around which the chain wraps, has a diameter of 1.6 feet1.6 \text{ feet}. The sailors push on the capstan bars at a horizontal distance of 4.0 feet4.0 \text{ feet} from the central axis of rotation. If the anchor chain exerts a steady pull of 1,500 pounds1,500 \text{ pounds}, what is the total effort force the sailors must apply to the bars to keep the anchor moving at a constant speed? (Assume 100% efficiency and ignore friction)

  1. A
    600 pounds600 \text{ pounds}
  2. B
    7,500 pounds7,500 \text{ pounds}
  3. 300 pounds300 \text{ pounds}Cevap
  4. D
    3,750 pounds3,750 \text{ pounds}

Cevap

300 pounds300 \text{ pounds}
A capstan operates as a wheel and axle mechanism. The effort is applied at a distance of 4.0 feet4.0 \text{ feet} (the wheel's radius), and the load is pulled by a drum with a radius of 0.8 feet0.8 \text{ feet} (half of the 1.6-foot1.6\text{-foot} diameter). The Ideal Mechanical Advantage is the ratio of these radii: 4.0/0.8=54.0 / 0.8 = 5. To find the required effort force, divide the 1,500-pound1,500\text{-pound} load by the mechanical advantage of 55, which equals 300 pounds300 \text{ pounds}.

Adım Adım Çözüm

1
Determine the radii of both the wheel (effort arm) and the axle (drum).
Wheel radius (RR) = 4.0 feet4.0 \text{ feet}. Axle radius (rr) = 1.6 feet/2=0.8 feet1.6 \text{ feet} / 2 = 0.8 \text{ feet}.
The Ideal Mechanical Advantage (IMA) of a wheel and axle depends on the ratio of their radii. The problem provides the diameter of the drum, which must be halved.
2
Calculate the Ideal Mechanical Advantage (IMA) of the capstan system.
IMA=Rr=4.00.8=5IMA = \frac{R}{r} = \frac{4.0}{0.8} = 5.
Because the effort is applied to the larger wheel (the bars), the system multiplies the input force by a factor of 5.
3
Calculate the required effort force to overcome the load.
Effort Force=LoadIMA=15005=300 pounds\text{Effort Force} = \frac{\text{Load}}{IMA} = \frac{1500}{5} = 300 \text{ pounds}.
The effort force is the total load divided by the mechanical advantage.

Anahtar Kavram

Ideal Mechanical Advantage of a Wheel and Axle
Bu soruyu puanla