Question
Asked Nov 7, 2019
18 views

A 12 gram CD with a radius of 6 cm rotates with an angular speed of 34 rad/s. A.) What is its kinetic energy? B.) If its kinetic energy is to be quadrupled, should its angular speed be doubled, quadrupled, or increased by a factor of 16? C.) Calculate the angular speed required to quadruple the kinetic energy the CD had in part A.).

check_circle

Expert Answer

Step 1

The moment of inertia of the CD is

help_outline

Image Transcriptionclose

mi 2 (0.012)(0.06) 2 2.16x10 kgm2

fullscreen
Step 2

(A).

Kinetic energy is

help_outline

Image Transcriptionclose

KE = - I@ 2 1 (2.16x 10)(34) 2 1.248 x 10 J

fullscreen
Step 3

(B).

If its kinetic energy is to be quadru...

help_outline

Image Transcriptionclose

E2 4E E 2 If its kinetic energy is to be quadrupled, then the angular speed is doubled

fullscreen

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in

Science

Physics

Angular Motion

Related Physics Q&A

Find answers to questions asked by student like you
Show more Q&A
add