pharm89
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Homework Statement
I just would like to know if I'm using the right procedure to solve these problems.
(a) Suzanne is skiing with a velocity of 18.0 m/s (N30.0 degrees W). What is the (N) component of her velocity vector?
(b) TIm is running cross-country at 6.4 m/s (S) when he completes a wide turn and continues at 5.8 m/s (W). What is his change in velocity?
Homework Equations
Cos(theta) = adjacent / hypotenuse
velocity = V2 - V1
use of Pythagorean theorum formula
The Attempt at a Solution
(a) Given:
velocity = 18.0 m/s
30 degrees
Required: Vn
Analysis:
cos(theta) = adjacent/hypotenuse
Cos30 degrees = Vn / 18 m/s
Vn = (18.0 m/s) (Cos30 degrees)
=15.6 m/s
(b) Given:
V1 = 6.4 m/s (E)
V2 = 5.8 m/s W
Required: change in velocity
Analysis: velocity = V2 - V1
=V2 + (-V1)
=V2 - V1
use the pythagorean theorum to determine the magintude of the velocity vector.
V^2 = (5.8)^2 + (6.4)^2
=33.64 + 40.96
=74.6 m^2 s^2
=8.64 m/s
Then determine the direction of the velocity vector.
Tan (theta) = 5.8 m/s / 6.4 m/s =0.91
=tan-10.91
=42.3 degrees
Therfore his change in velocity is 8.64 m/s (S 42.3 degrees W)
Any help is always appreciated.
Thanks
Pharm 89
