posted by Adam on .
Suppose you would like to cross a 209-foot wide river in a boat. Assume that the boat can travel 32 mph relative to the water and that the current is flowing west at the rate of 6 mph. If the bearing chosen is chosen so that the boat will land at a point exactly across from its starting loin, how long will it take for the boat to make the crossing? Give your answer to the nearest second.
if the boat travels s seconds,
1 km/hr = 1.4667 ft/s
209^2 + (6*1.4667s)^2 = (32*1.4667s)^2
s = 4.5 sec
1 mile/hr=1.46667 ft/sec. The KM here is a typo. The rest o the problem is good and correct. Giving direction on how to draw a diagram to visualize would have been be great.
Thanks and keep up the good work.