Homework Help: Relative velocity

1. Dec 2, 2009

Delta G

1. The problem statement, all variables and given/known data

A plane flies flies into a 65 mi/h headwind. On the return trip from B to A, the wind velocity is unchanged. The trip from B to A takes 65 min less than the trip from A to B. What is the airspeed (assumed constant) of the plane?

a. 480 mi/h
c. 530 mi/h
b. 610 mi/h
d. 400 mi/h

2. Relevant equations

?

3. The attempt at a solution

65 min = 1.08 hrs
time from A to B = 2300 mi / 65 mi/hr = 35.4 hrs
time from B to A = 35.4 hrs - 1.08 hrs = 34.4 hrs

Not sure if I am doing it correctly and not sure where to go from here.

Last edited: Dec 2, 2009
2. Dec 2, 2009

kuruman

First off, where did you get 2300 miles? No such number is mentioned in the problem statement. Secondly, even if you were told that the distance is 2300 miles, the plane cannot be flying at 65 mi/h if the headwind is also 65 mi/h because it would not move at all. Call the speed of the plane v and write two equations, one for the time A to B and one for the time B to A.