
Physics Physics Forum 
 LinkBack  Thread Tools  Display Modes 
February 2nd, 2015, 10:56 AM  #1 
Member Joined: Jul 2014 From: Seattle Posts: 96 Thanks: 2  A mechanics problem I'm a bit confused about.
I have a question that states that a varying force of magnitude 4020t N is applied to a mass of 10kg... Therefore I say by F = ma, that a = 42t  right? It then says that the mass is moving forward with velocity 5 meters per second through the origin when t = 0. I'm supposed to find s(t) including the constant... Therefore I integrate acceleration to get v = 4t  t^2 + c where c obviously equals 5 based on the velocity at t = 0. I then integrate that to find the s(t) and get s = 2t  (1/3)t^3 + 5t + d, right? The issue is, I don't know how to find the value of d? The last part of the question is really confusing. It says I am supposed to find the furthest distance in the positive direction from the origin... I have no idea how to answer that. 
February 2nd, 2015, 11:54 AM  #2  
Math Team Joined: Dec 2013 From: Colombia Posts: 7,671 Thanks: 2651 Math Focus: Mainly analysis and algebra  Quote:
It says the mass is moving forward with velocity 5 meters per second through the origin when t = 0 so that means that $s(0) = 0$ i.e. the mass is at the origin at $t=0$. Finding when the mass is furthest from the origin is about finding the maximum value of $s(t)$. This occurs at a point when $s'(t) =v(t)= 0$ and $s''(t) = a(t) \lt 0$.  
February 2nd, 2015, 01:10 PM  #3  
Member Joined: Jul 2014 From: Seattle Posts: 96 Thanks: 2  Quote:
 

Tags 
bit, confused, mechanics, problem 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
MECHANICS PROBLEM  abdulrehmanshaah  Applied Math  0  February 9th, 2014 05:16 AM 
Vector / mechanics problem, very confused  mikev  Algebra  1  April 14th, 2013 11:36 PM 
Mechanics Problem  rolling pin and friction  sumukid  Physics  2  August 12th, 2011 12:24 AM 
HELP!!! Mechanics problem  SarahB5  Physics  2  December 12th, 2008 06:45 AM 
HELP!!! Mechanics problem  SarahB5  Applied Math  0  December 31st, 1969 04:00 PM 