Vector A points in the negative x direction. Vector B points at an angle of 30° above the positive x axis. Vector C has a magnitude of 17 m and points in a direction 42.0° below the positive x axis. Given that A + B + C =0, find the magnitudes of A and B.
Solution:
Given, vector A points in the negative x direction
Vector B points at an angle of 30° above the positive x axis.
Vector C has a magnitude of 17m and points in a direction of 42° below the positive x axis.
A + B + C = 0
We have to find the magnitude of A and B.
Vector A in the negative x direction is -a.
Vector B = bcos30° - bsin30°
Vector C = 17cos42° - 17sin42°
The system of equations are
17 cos 42° + b cos 30° - a = 0 --- (1)
17 sin 42° - b sin 30° = 0 --- (2)
On solving (2),
17 sin 42° = b sin 30°
17(0.6691) = b (0.5)
11.3747 = 0.5b
b = 11.3747/0.5
b = 22.7494
|b| = 22.7494 m
Put the value of b in (1),
17(0.7431) + 22.7494(0.8660) - a = 0
12.6327 + 19.7009 = a
a = 32.33368
|a| = 32.3337 m
Therefore, the magnitudes of A and B are 32.3337m and 22.7494m.
Vector A points in the negative x direction. Vector B points at an angle of 30.0° above the positive x axis. Vector C has a magnitude of 17 m and points in a direction 42.0° below the positive x axis. Given that A + B + C = 0, find the magnitudes of A and B.
Summary:
Vector A points in the negative x direction. Vector B points at an angle of 30.0 ∘ above the positive x axis. Vector C has a magnitude of 17 m and points in a direction 42.0 ∘ below the positive x axis. Given that A + B + C = 0, the magnitudes of A and B are 32.3337m and 22.7494m.
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