Posted by karl on Thursday, August 7, 2014 at 6:09am.
A barge is being towed south at the rate 2 km/hr. A man on the deck walks from west to east at the rate 4ft/s. Find the magnitude and direction of the man's actual velocity.

trigonometry  Reiny, Thursday, August 7, 2014 at 7:46am
1 km = appr 3280.84 feet
2 km/h = 2(3280.84/3600) ft/s
= 1.82269 ft/s
let r be the resultant velocity
r^2 = 2^2 + 1.82269^2
r = √7.32219..
= appr 2.7 ft/s
tanØ = 1.82269/2 , where Ø is in my rightangled triangle
Ø = appr 42.34°
his direction is S 42.34° E
or by vectors
vector r = 2(cos270 , sin270) + 1.82269(cos0 , sin0)
= 2(0, 1) + 1.82269(1,0)
= (0,2) + (1.82269,0)
= (1.82269,2)
magnitude = √(1.82269^2 + (2)^2)
= 2.7 as above
direction:
tan k = 2/1.82269
k = 312.34° which is the same as S 42.34 W

trigonometry  Henry, Thursday, August 7, 2014 at 8:10pm
X = 4 Ft/s
Y = 2km/h = 2000m/3600s * 3.3Ft/m = 1.833 Ft/s
Tan A = Y/X = 1.833/4 = 0.45825
A = 24.62o = 24.62o South of East. =
65.38o East of South = Direction.
Magnitude = X/Cos A = 4/Cos(24.62) =
4.4 Ft/s.
Answer This Question
Related Questions
 math  A boat is travelling south at a rate of 18 km/h. A man walks across the ...
 Physics  A man walks the distance of 8km in a direction of 20degrees east the ...
 physics  A 1000kg barge is being towed by means of two horizontal cables. One ...
 Physics  a man walks 10km towards west and then 15 km towards south. Find the ...
 Physics  A boy walks 10 m due west and 10m due south.What is the displacement.[...
 Physics  Determine the magnitude and direction of the displacement if a man ...
 Physics  A man was lost in the woods. He wanders 3 km north, then 7 km east, ...
 Physics  A river flows due south with a speed of 2.00 m/s. A man steers a ...
 Physics  Consider a map oriented so that the x axis runs east–west (with east ...
 physics  A man walks 3 miles east in 1 hour at a constant velocity, then walks ...
More Related Questions