Newton's Second Law & Moment of Inertia Derivation?

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Homework Help Overview

The discussion revolves around deriving the expression for the moment of inertia using Newton's Second Law, with references to a lab experiment. The original poster shares their attempts and equations related to the problem.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to manipulate equations involving force, tension, and acceleration to derive the moment of inertia. Some participants question the necessity of calculus for understanding the problem, while others seek clarification on the physical system being analyzed.

Discussion Status

The discussion is ongoing, with participants exploring the relevance of calculus and confirming the physical system's consistency with the lab experiment. There is no explicit consensus on the approach yet, but questions about the system and prerequisites are being addressed.

Contextual Notes

Participants note that the problem is based on a specific physical system used in a lab, and there is a mention of effective mass in the equations. The original poster expresses confusion about certain terms and calculations.

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Homework Statement


We did something very similar to this in lab

http://webenhanced.lbcc.edu/physte/phys2ate/2A LAB HANDOUTS/Moment of Inertia.pdf

Use Newton's Second to derive the expression for the experimentally determined moment of inertia

Homework Equations


Newton's Second Law is F=m*a

s=(1/2)*a*t^2

Experimentally Moment of Inertia

I=r^2(m((gt^2/2s)-t) - mf)

Trying to get to this ^

mf= mass effective not much meaning just mass in kg
If it confusing the gt^2 is divided by 2s then it is subtracted by t and multiplied by r^2 and then minus mf

Torque= F*r= m*r*a

T= (mf + m)(g - a) = tension

The Attempt at a Solution



T= (mf + m)(g - (2*s/t^2))

T= (mf + m)((1/2)(a*t^2) - a)

T= (mf + m)(a((1/2)*t^2 - 1)

I am stuck write here
 
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Is calculus is a prerequisite for this course?
 
Pythagorean said:
Is calculus is a prerequisite for this course?

yes it is Physics Calculus Based 2211K
 
Calc may not be necessary.

So what's the physical system you're doing in this problem? Is it the same exact system as in the lab?
 
Pythagorean said:
Calc may not be necessary.

So what's the physical system you're doing in this problem? Is it the same exact system as in the lab?

yes it is the exact same system
 

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