
Algebra PreAlgebra and Basic Algebra Math Forum 
 LinkBack  Thread Tools  Display Modes 
June 9th, 2018, 09:33 PM  #1 
Newbie Joined: Jul 2017 From: KOLKATA Posts: 29 Thanks: 2  Relative velocity
While a boat cruises down a river, it crosses a wooden log at a particular point of time. Then the boat travels along the river for a time C and reverses its direction to travel upstream for a time T, when it meets the same wooden log, which has been freely drifting along the river all the while. If the engine of the boat has been working at the same power level throughout its journey, express T in terms of C. My answer came out: T = C. Could anyone please confirm as the answer given is roman Tau. Last edited by skipjack; June 10th, 2018 at 02:09 AM. 
June 9th, 2018, 09:54 PM  #2 
Senior Member Joined: Sep 2015 From: USA Posts: 1,974 Thanks: 1025 
Let the boat meet the log the first time at $t=0$ Also let the boat's velocity in still water be $v_b$ The log drifts at the velocity of the current $v_c$ $C(v_b + v_c) + T(v_cv_b) = v_c (C+T)$ This does simplify to $T=C$ 
June 9th, 2018, 10:02 PM  #3 
Newbie Joined: Jul 2017 From: KOLKATA Posts: 29 Thanks: 2 
Many Thanks . I got confused with the answer given in the book.


Tags 
relative, velocity 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Relative Mathematics  Conway51  Number Theory  25  December 6th, 2017 05:48 PM 
Initial Velocity, Final Velocity  IzzyD  Physics  3  June 3rd, 2017 12:29 PM 
N relative photons: N1 dimensional velocity space  Loren  Physics  3  October 15th, 2016 01:54 PM 
Obtaining angular velocity given linear velocity and center of rotation 3D  quarkz  Calculus  0  April 18th, 2014 05:34 AM 
relative min or max or neither  ArmiAldi  Calculus  4  March 11th, 2008 04:42 PM 