Exam (elaborations)

Lab-5-Experiment 5: Rotational Inertia of Disk and Ring

3 views 0 purchase

Course
ENTK 8953

Institution
Sheridan College Institute Of Technology And Advanced Learning ( )

Experiment 5: Rotational Inertia of Disk and Ring EQUIPMENT REQUIRED - DataStudio Program - Mass and Hanger Set - PASCO Interface (see Note) - Paper Clips (for masses < 1 g) - Rotational Inertia Accessory (ME-8953) - Balance - Photogate/Pulley System - Calipers Purpose The purpose of this...

[Show more]

Preview 2 out of 6 pages

View example

Uploaded on November 22, 2022
Number of pages 6
Written in 2022/2023
Type Exam (elaborations)
Contains Questions & answers

experiment 5 rotational inertia of disk and ring

CA$9.08

Added

Add to cart Add to wishlist

100% satisfaction guarantee
Immediately available after payment
Both online and in PDF
No strings attached

012-05293F Complete Rotational System

Experiment 5: Rotational Inertia of Disk and Ring

EQUIPMENT REQUIRED
Note: If you are
- DataStudio Program - Mass and Hanger Set
using a PASPORT
- PASCO Interface (see Note) - Paper Clips (for masses < 1 g) interface, you will
- Rotational Inertia Accessory (ME-8953) - Balance also need a Digital
- Photogate/Pulley System - Calipers Adapter (PS-2159)

Purpose
The purpose of this experiment is to find the rotational inertia of a ring and a disk experimentally
and to verify that these values correspond to the calculated theoretical values.

Theory
Theoretically, the rotational inertia, I, of a ring about its center of mass is given
by:
R1 R2
1 2 2
I = --- M ( R 1 + R2 )
2

where M is the mass of the ring, R1 is the inner radius of the ring, and R2 is the
outer radius of the ring. See Figure 5.1.
The rotational inertia of a disk about its center of mass is given by:
Figure 5.1: Ring
1 2
I = --- MR
2

where M is the mass of the disk and R is the radius of the disk. The rotational inertia of a disk
about its diameter is given by:
1 2
I = --- MR
4

R

R

Disk about center of Mass Figure 5.2: Disk about Diameter

To find the rotational inertia experimentally, a known torque is applied to the object and the
resulting angular acceleration is measured. Since τ = Iα,
τ
I = ---
α

31

, Complete Rotational System 012-05293F

where α is the angular acceleration which is equal to a/r and τ is the torque caused by the
weight hanging from the thread which is wrapped around the base of the apparatus.

τ = rT

where r is the radius of the cylinder about which the thread is wound and T is the tension in
the thread when the apparatus is rotating.
Applying Newton’s Second Law for the hanging mass, m, gives (See Figure 5.3)

ΣF = mg – T = ma

rotational disk T

a
"A" base
hanging mg
mass

Figure 5.3: Rotational Apparatus and Free-Body Diagram
Solving for the tension in the thread gives:

T = m( g – a )

Once the linear acceleration of the mass (m) is determined, the torque and the angular
acceleration can be obtained for the calculation of the rotational inertia.

Setup
mass ring
1. Remove the track from the Rotating Platform and place the
disk directly on the center shaft as shown in Figure 5.4. The 10-spoke pulley with
rotational
photogate head
side of the disk that has the indentation for the ring should disk
be up.
2. Place the ring on the disk, seating it in this indentation.
3. Mount the Photogate/Pulley System to the base and connect
it to a PASCO interface. "A" base
4. Attach a thread to the top step of the three-step pulley on the mass and
hanger
Rotational Apparatus shaft and suspend the string over the
pulley of the Photogate/Pulley System. Attach a hanger and
mass to the end of the thread.
5. Start the DataStudio program. Figure 5.4: Set-up for Disk and Ring

Procedure
Measurements for the Theoretical Rotational Inertia
1. Weigh the ring and disk to find their masses and record these masses in Table 5.1.
2. Measure the inside and outside diameters of the ring and calculate the radii R1 and R2. Record in
Table 5.1.
3. Measure the diameter of the disk and calculate the radius R and record it in Table 5.1.

32

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller Abbyy. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for CA$9.08. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

73314 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling