12 In 1980, over San Francisco Bay, a large yo-yo was released from a crane. The

Question

12 In 1980, over San Francisco Bay, a large yo-yo was released from a crane. The 116 kg yo-yo consisted of two uniform disks of radius 32 cm connected by an axle of radius 3.2 cm. What was the magnitude of the acceleration of the yo-yo during (a) its fall and (b) its rise? (c) What was the ten- sion in the cord on which it rolled? (d) Was that tension near the cord's limit of 52 kN? Suppose you build a scaled-up ver sion of the yo-yo (same shape and materials but larger). (e) Will the magnitude of your yo-yo's acceleration as it falls be greater than, less than, or the same as that of the San Francisco yo-yo? (f) How about the tension in the cord?

Explanation / Answer

? = 116kg * 9.8m/s² * 0.032m = 36.38 N·m

I = ½mr² = ½ * 116kg * (0.32m)² = 5.94 kg·m²

? = 36.38 N·m = I? = 5.94kg·m² * ?

? = 6.125 rad/s²

a = ?r = 6.125rad/s² * 0.032m = 0.196 m/s² down

b) Assuming energy is conserved, 0.196 m/s² up

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.