Register to reply

Atwood Machine Lab calculations

by ~christina~
Tags: atwood, calculations, machine
Share this thread:
Oct15-07, 01:09 AM
PF Gold
~christina~'s Avatar
P: 824
1. The problem statement, all variables and given/known data
My results are coming out funny and I was wondering if I was doing something wrong.
I have to find acceleration due to gravity.

one of my values ....

m2 (decending mass) = 60g
m1(ascending mass)= 50g

distance traveled= 95.3cm or .953m

time traveled average= 19.60s

total mass (m1 + m2)= 110g

2. Relevant equations
am (measured)= 2y/t^2

at(theoretical) = (m2-m1)g/(m1 + m2)

3. The attempt at a solution

well I try to find g from the am (or measured acceleration) by using the am and plugging into the theoretical accleration (at) equation but find g instead of a.

am= 2(.953m)/(19.60s)^2
am= 0.00496m/s^2

then plugging into the at equation..

am(m1+m2)/ (m2-m1)= g

[0.00496m/s^2 (110g)]/ 10g= 0.54m/s^2 ===> this is so not 9.8m/s^2..

Basically that's it..except I also find the theoretical acelleration from using 9.8m/s^2 which would be the ideal and find that but I get...

at= (m2-m1)g/ (m1 + m2)

at= (10g)(9.8m/s^2) / (110)= .891m/s^2 for acceration.

I'm supposed to ignore the friction..

I really don't know why it comes out like this..Am I doing anything incorrectly??
I have to get this right or explain why it went wrong since this is for a lab report.

Thank You .
Phys.Org News Partner Science news on
Scientists develop 'electronic nose' for rapid detection of C. diff infection
Why plants in the office make us more productive
Tesla Motors dealing as states play factory poker
Oct15-07, 03:53 AM
Sci Advisor
PF Gold
P: 4,980
You seem to be doing the analysis correctly. I'd guess that there was some sort of unwanted resistance in the pulley system, because 19.6 seconds is a long time to travel 1 meter.
Oct15-07, 07:19 AM
PF Gold
~christina~'s Avatar
P: 824
Oh..okay Thank Kurdt! =)

Register to reply

Related Discussions
Help atwood machine Introductory Physics Homework 3
Atwood machine help Introductory Physics Homework 7
Atwood Machine Introductory Physics Homework 4
Atwood Machine Introductory Physics Homework 24