|
Title: Find the magnitude of the velocity of the canoe relative to the river? Post by: tonio613 on Jan 9, 2013 A canoe has a velocity of 0.340 m/s southeast relative to the earth. The canoe is on a river that is flowing 0.570 m/s east relative to the earth.
Find the direction of the velocity of the canoe relative to the river. Express your answer as an angle measured south of west. Can't seem to get the answer correctly. Title: Find the magnitude of the velocity of the canoe relative to the river? Post by: Firas on Jan 9, 2013 for the velocity of the canoe relative to the Earth, it says southeast..u need an angle for that before u can figure out the velocity of the canoe relative to the river.
Title: Re: Find the magnitude of the velocity of the canoe relative to the river? Post by: momo29 on Jan 11, 2013 Draw a triangle ABC in which:
AB = 0.34 SE, representing the velocity of the canoe relative to earth; AC = 0.57 E, representing the velocity of the river relative to earth. CB is the vector which added to AC gives AB. That is the velocity of the boat relative to the river. Noting that angle BAC = 45deg, and using the cosine rule: CB = sqrt[ 0.34^2 + 0.57^2 - 2 * 0.34 * 0.57 cos(45) ] = 0.408m/sec. Using the sine rule: sin(ACB) = 0.34 * sin(45) / 0.408 Angle ACB = 36.11deg. As AC points E, this direction is: 90 - 36.11 = S 53.89 deg. W. **source-straight from yahoo |