In the following apparatus, the auxiliary platter is dropped onto the main platt

Question

In the following apparatus, the auxiliary platter is dropped onto the main platter. The main platter has a rotational inertia I_M and an initial angular velocity omega_O. The auxiliary platter has a rotational inertia I_A and is initially not spinning. a.) Explain why the two platters will have the same final angular velocity. b.) What implications does your answer to Part (a) have for the conservation of angular momentum in this system? For the conservation of rotational kinetic energy? c.) Using conservation of angular momentum, find an expression for the final angular velocity of the system assuming the two platters have the same final angular velocity. d.) Using your answer to Part (c) above, show that the ratio of final kinetic energy to initial kinetic energy is given by the expression below:

Explanation / Answer

a) after the auxiliary one dropped, Both of them are the part of the same object,so will rotate together and hence will have same angular velocity

b) Angular momentum is conserved before and after, Before the momentum is only because of main platter, after the same angular momentum will be shared by both the platters.

The rotational KE is not conserved as they will become slow.

c) Im w0 + Ia*0 = (Im+Ia) w

w= Im w0/(Im+Ia)

d) They have given some expression , which you forgot to put here. Anyway use the ratio KE= 0.5 I w^2 do it before and after. you will get it. If you on't get it , post it again with that expression !

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

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