Mirror physics homework

In summary, the conversation is about finding the minimum dimensions for a rear-view mirror in a car so that the driver can see the entire width and height of the rear window without moving her head. The discussion involves setting up triangles and using the concept of similar triangles to solve the problem. The attached diagram is used as both a side view and a top view to determine the necessary distances and angles. The conversation ends with the speaker thanking the other person for their help.
  • #1

Homework Statement

The rear window in a car is approximately a rectangle, 1.3 m wide and 0.30 m high. The inside rear-view mirror is 0.61 m from the driver's eyes, and 1.37 m from the rear window. What are the minimum dimensions for the rear-view mirror if the driver is to be able to see the entire width and height of the rear window in the mirror without moving her head?

I tried setting up triangles to solve this but it got very confusing, because I did not know what the legs would be for many of the dimensions. I mainly need help in getting started.
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  • #2
Try the set of triangles drawn in the attachment. Draw and label horizontal and vertical lines for each distance you know. And try and work out all of the other distances and angles.

Notice that if you grabbed the point of the triangle at the eye and swung it around to the left you would have one big triangle. In other words, the angles which look the same are the same.

You will need to use this diagram as both a side view and a top view.
For instance, with the side view, the vertical line on the left represents the mirror height and the vertical line on the right represents the rear window height (a distance of 0.3m).

With the top view, the vertical line on the left represents the mirror width and the vertical line on the right represents the rear window width (a distance of 1.3m).

I believe the easiest way to find the height and width of the mirror will be using what you know about "similar triangles".


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  • #3
Thank you soooo much! That made a lot of sense and it really helped!

1. What is mirror physics homework?

Mirror physics homework is a type of assignment that involves studying the properties and behaviors of mirrors. This may include topics such as reflection, refraction, and image formation.

2. Why is it important to study mirror physics?

Understanding mirror physics is essential in many fields, including optics, astronomy, and engineering. It allows us to manipulate and control light, which is crucial in various applications such as telescopes, cameras, and lasers.

3. What are some common challenges in mirror physics homework?

Some common challenges in mirror physics homework include grasping the abstract concepts, applying mathematical equations, and interpreting results accurately. It may also involve conducting experiments and analyzing data.

4. How can I improve my understanding of mirror physics?

To improve your understanding of mirror physics, it is essential to practice solving problems and conducting experiments. You can also seek additional resources, such as textbooks, online tutorials, and working with a tutor or study group.

5. What are some real-world applications of mirror physics?

Mirror physics has many real-world applications, including the design and construction of various optical instruments, such as telescopes, microscopes, and cameras. It is also used in the development of optical fibers for telecommunication and in medical imaging technologies.

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