Two ladybugs, each with mass m, sit at opposite ends of a light rod of length L

Question

Two ladybugs, each with mass m, sit at opposite ends of a light rod of length L that is rotating about a frictionless axle passing through its center. The system's angular speed is omega. The ladybugs then slowly walk along the rod towards each other, until they are both the located a distance of L/4 away from the center of the rod. What is the final angular speed of the system, expressed as a multiple of initial angular speed, omega? The final angular velocity of the system omega_final, is equal to A. omega/16 B. omega/4 C. omega/2 E. 2 omega F. 4omega G. 16 omega what physics principle allows you to calculate the final angular speed of the system from the information given above? Circle ALL apply. A. Conservation of angular momentum B. Conservation of linear momentum C. Conservation of mechanical energy D. None. This is a trick question. The final angular speed cannot be determined from the information given above.

Explanation / Answer

here,

initial angular speed of system, w1

initial moment of inetia os system I1
I1 = inertia of rod + inertia of bugs
I1 = ml^2/12 + 2 * m * (l/2)^2
I1 = ((m*l^2)/12 + ml^2 )

Final moment of inetia os system I1
I2 = inertia of rod + inertia of bugs
I2 = ml^2/12 + 2 * m * (l/4)^2
I2 = (ml^2/12 + (m*l)^2/8)

From conservation of angular momentum we have :
before = after

w1 * I1 = w2 * I2

final angular speed, w2 = w1 * I1 / I1

final angular speed, w2 = (w1 * ((m*l^2)/12 + ml^2 ) / (ml^2/12 + (m*l)^2/8))

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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