
Calculus Calculus Math Forum 
 LinkBack  Thread Tools  Display Modes 
October 31st, 2017, 08:31 AM  #1 
Member Joined: Oct 2016 From: Sverige Posts: 32 Thanks: 2  Calculate mass along thread (lineintegral) I've tried to solve this 4 times already, what am I doing wrong? 
October 31st, 2017, 08:41 AM  #2 
Senior Member Joined: Sep 2015 From: USA Posts: 2,120 Thanks: 1101 
You're doing it wrong :P There's no force here to dot with $dr$ You just have to calculate the differential length along the string and multiply it by the density. I.e. $m = \displaystyle \int_0^1 ~(1+t)\left\\dfrac{dr}{dt}\right \~dt$ see if you can chug through the integral. 
October 31st, 2017, 10:44 AM  #3 
Member Joined: Oct 2016 From: Sverige Posts: 32 Thanks: 2 
integral of (1+t)sqrt(9 + 36t + 36t^2) ? **** me this is the second exercise in this subject, doing mega complex integrals is not part of the course. Is there a simpler way? 
October 31st, 2017, 11:03 AM  #4 
Senior Member Joined: Sep 2015 From: USA Posts: 2,120 Thanks: 1101  

Tags 
calculate, lineintegral, mass, thread 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Calculating the line integral of a curve given line segments  nomad609  Calculus  0  October 23rd, 2016 11:39 AM 
Calculate the mass  Chikis  Algebra  2  January 29th, 2015 04:34 AM 
triple integral for mass  frankpupu  Calculus  1  February 19th, 2012 07:12 AM 
calculate point on a line  olibara  Algebra  9  December 28th, 2011 11:51 AM 
Calculate size by knowing mass?  JohnSmith222  Physics  6  April 10th, 2008 04:58 PM 