Final answer:
Vector ra has a magnitude of 49.0 m and points 20° below the positive x-axis, while vector rb has a magnitude of 75 m and points 45.0° above the positive x-axis. The properties of these vectors include their magnitudes and directions, and their components can be calculated using trigonometric functions with their respective angles.
Step-by-step explanation:
The student is asking about the properties of two position vectors that lie in a plane with respect to the positive x-axis. Vector ra points 20° below the positive x-axis and has a magnitude of 49.0 m. The vector rb points 45.0° above the positive x-axis and has a magnitude of 75 m.
To analyze these vectors, we use the components along the x- and y-axes. Components are found using trigonometric functions: for vector ra, since it is below the x-axis, its y-component will be negative. On the other hand, vector rb will have positive components in both the x and y directions because it is above the x-axis.
The vector's x-component can be calculated using the cosine of the angle (cosθ), and the y-component can be found using the sine of the angle (sinθ). For example, if ra has a magnitude of 49.0 m and it makes a 20° angle below the x-axis, its x-component would be 49.0 m * cos(20°) and its y-component would be -49.0 m * sin(20°), as the y-component is negative.