May 11th, 2019, 10:03 AM  #1 
Member Joined: Feb 2018 From: Iran Posts: 52 Thanks: 3  Average velocity I found the average velocity this way x0=120 X=x0+vt X=120+0.5*80 X=160 Vav= 160÷5=32 But answer is not correct according to my book why? 
May 11th, 2019, 11:08 AM  #2 
Math Team Joined: Jul 2011 From: Texas Posts: 3,002 Thanks: 1588 
since travel is in one direction only, average velocity = average speed average speed = (total distance traveled)/(total travel time) $\bar{v} = \dfrac{120 \,km + 80 \, km}{5 \,hrs} = 40 \, km/hr$ 
May 11th, 2019, 08:02 PM  #3 
Member Joined: Feb 2018 From: Iran Posts: 52 Thanks: 3  I am so sorry I thought that 80km is 80 km/h now I got it thanks
Last edited by Elize; May 11th, 2019 at 08:31 PM. 
May 11th, 2019, 08:28 PM  #4 
Member Joined: Oct 2018 From: USA Posts: 88 Thanks: 61 Math Focus: Algebraic Geometry  It's given in the problem, $120$ km in the first 2 hours, $0$ km for 2.5 hours and $80$ km in 0.5 hours. This gives a total distance of $120+0+80$ as skeeter says.
Last edited by skipjack; May 11th, 2019 at 11:02 PM. 

Tags 
average, velocity 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
What is the probability that the average velocity is ≥ 10^(−9 ) cm/sec?  poopeyey2  Advanced Statistics  2  October 26th, 2017 06:34 PM 
average value of the square of the velocity  ashlegen  Algebra  4  February 17th, 2014 01:10 AM 
Average Velocity over [a,b]  gorgekiter  Calculus  3  October 20th, 2013 05:54 PM 
Hydrology  Average groundwater flow velocity  sayzteff  Physics  0  November 24th, 2012 07:13 AM 
average velocity  mathman2  Calculus  10  October 19th, 2009 04:15 PM 