(adsbygoogle = window.adsbygoogle || []).push({}); 2D Kinematics Please Help! I tried so hard

Relative to the ground, a car has a velocity of 17.3 m/s, directed due north. Relative to this car, a truck has a velocity of 20.5 m/s directed 48.5 ° south of east. Find the (a) magnitude and (b) direction of the truck's velocity relative to the ground. Give the directional angle relative to due east.

I got:

Vcg = 0x + 17.3y

Vtg = 20.5 cos (45) - 20.5 sin(45)

The resultant is: 14.496x + 2.804y

So, by the Pythagorean theorem, Vtg = 14.765

(But that's wrong)

And the direction would be: Inverse tangent of (2.804/14.496)

so it's 10.948 degrees

And that's wrong too.

I also tried it with adding the 20.5 sin(45) on the Vtg part, but those answers are wrong too. I dont know what to do!

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# Homework Help: 2D Kinematics I tried so hard

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