How to solve for vectors components

In summary, the car's displacement can be calculated by adding the given vectors in terms of their components. The car drives north at 48mi/h for 10 min, then turns east and goes 5.0 mi at 66mi/h, and finally moves southwest at 36mi/h for 6.0 min. The total displacement is the sum of these vectors, which can be plotted on a graph to find the magnitude and orientation of the final displacement vector. The positive x and y axes are directed to the east and north, respectively.
  • #1
warnexus
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Homework Statement


A car drives north at 48mi/h for 10 min and then turns east and goes 5.0 mi at 66mi/h . Finally, it goes southwest at 36mi/h for 6.0 min.

Determine the car's displacement.

Assume that the positive x and y axes are directed to the east and north, respectively.
Answers should be in x and y components of the resultant

Homework Equations


x component aka i hat lies in the x-axis
y component aka j hat lies in the y axis

The Attempt at a Solution


since the car is going north at that velocity. the magnitude of that vector is 8 mi. When the car goes east, the magnitude is given as 5.0mi. when the car moves southwest, the magnitude is 3.6mi.

Not sure if the graph is right but I thought I get feedback on it.

vector_zps56d5285d.png
 
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  • #2
The total displacement is merely the sum of the given vectors. Write each vector in terms of its components. Note that a direction like southwest implies a 45 degree angle between south and west, this should help you write the components.

To find a vector component in a direction, you need to know the angle between the vector and that direction.
 
  • #3
since the car is going north at that velocity. the magnitude of that vector is 8 mi. When the car goes east, the magnitude is given as 5.0mi. when the car moves southwest, the magnitude is 3.6mi.

correct...

so plot these on graph paper, tail to head [ector arrow point], and connect the final head to the origin...the length is your final magntiude and the angle you measure relative to horizontal records the orientation. ..so for example, go 8 up [vertical], from there 5 down and to the right at 45 degrees 5, then horizontal right from there 3.6...
 
  • #4
I thought it was 5 horizontal right and 3.6 down left. Thanks for the feedback. i added a picture on what I did with the vector components. I feel super stuck on this problem.
 
  • #5


I would like to point out that the given information is incomplete. In order to solve for the car's displacement, we also need to know the starting point of the car's journey. Without this information, we cannot accurately determine the displacement in terms of x and y components.

Assuming that the starting point is the origin (0,0), we can use the given information to calculate the displacement. The car's displacement can be represented as a vector with its tail at the origin and its head at the final position of the car.

To calculate the x and y components of the displacement, we can use the following equations:

x component = magnitude of displacement * cos(theta)
y component = magnitude of displacement * sin(theta)

In this case, the magnitude of displacement can be calculated by adding the magnitudes of the individual vectors (8 mi, 5.0 mi, and 3.6 mi) and the angle theta can be determined by using trigonometry.

Therefore, the x component of the displacement would be 8 mi + 5.0 mi * cos(theta) and the y component would be 5.0 mi * sin(theta) - 3.6 mi.

I would also like to suggest that instead of using a graph, it would be more accurate to use vector addition to calculate the displacement. This involves drawing the individual vectors to scale and using the parallelogram method to determine the resultant vector, which represents the displacement of the car.
 

1. What are vector components and why do we need to solve for them?

Vector components refer to the individual parts of a vector, which is a quantity that has both magnitude and direction. We need to solve for vector components in order to break down a vector into its horizontal and vertical components, which can be useful in solving problems involving motion and forces.

2. How do I determine the horizontal and vertical components of a vector?

To determine the horizontal and vertical components of a vector, you can use trigonometry. The horizontal component is equal to the magnitude of the vector multiplied by the cosine of the angle it makes with the horizontal axis. Similarly, the vertical component is equal to the magnitude of the vector multiplied by the sine of the angle.

3. Can vector components be negative?

Yes, vector components can be negative. This indicates the direction of the component is in the opposite direction of the positive axis. For example, a vector with a horizontal component of -5 would be pointing to the left, while a vector with a vertical component of -3 would be pointing downwards.

4. What is the difference between vector components and vector magnitude?

Vector components refer to the individual parts of a vector, while vector magnitude refers to the overall size or length of the vector. Vector components are expressed as numbers with units, while vector magnitude is a single number without units.

5. Can I use vector components to solve for the resultant vector?

Yes, you can use vector components to solve for the resultant vector. The resultant vector is the combination of all the individual vector components. By using trigonometry and the Pythagorean theorem, you can find the magnitude and direction of the resultant vector using the individual vector components.

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