A Coast Guard ship is traveling at a constant velocity of 4.25 m/s, due east, re
ID: 1327161 • Letter: A
Question
A Coast Guard ship is traveling at a constant velocity of 4.25 m/s, due east, relative to the water. On his radar screen the navigator detects an object that is moving at a constant velocity. The object is located at a distance of 2305 m with respect to the ship, in a direction 32.5° south of east. Six minutes later, he notes that the object's position relative to the ship has changed to 1115 m, 56.5° south of west. What are the magnitude and direction of the velocity of the object relative to the water? Express the direction as an angle with respect to due west.
m/sExplanation / Answer
let East be +x axis
let the initial poistion of gaurd is a orogin.
so, initial cordinates of object.
x1 = 2305*cos(32.5) = 1944 m
y1 = -2305*sin(32.5) = -1238.5 m
finalposition of the coardites,
x2 = 6*60*4.25 - 1115*cos(56.5) = 914.6 m
y2 = - 1115*sin(56.5) = -930 m
now diplacemt of object, d = sqrt((x2-x1)^2 + (y2-y1)^2)
= sqrt((914.6 - 1944)^2 + (-930 - (-1238.5))^2)
= 1074.6 m/s
velocity = dispalcemnt/time taken
= 1074.6/(6*60)
= 2.99 m/s
direction, theta = tan^-1((y2-y1)/(x2-x1))
= tan^-1((-930+1238.5)/(914.6 - 1944))
= 16.7 degrees south of west
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.