Question #5d526
1 Answer
Sep 22, 2015
The relative velocity is 39.39Km/hr
Explanation:
This is a problem of relativity,
Assumption 1: The ferry is travelling at an angle exactly 45 degrees from east
Assumption 2: The launch is travelling at an angle exactly -90 degrees from east
We have to find out the east and north components of the ferry
east = 20cos45 = 14.14Km/hr
north = 20sin45 = 14.14Km/hr
now we add the north component to the velocity of the launch as they are in opposite directions
so we have the north component w.r.t the launch as 15 + 14.14 = 29.14Km/hr
and the east component remains to be 14.14Km/hr
so the net velocity is (29.14^2+14.14^2)^0.5 = 39.39Km/hr
