- #1
bomberkid
- 14
- 0
Homework Statement
Hi please help me with these 2 ray diagrams... the questions is as stated in the attachment..i have no idea where to start drawing and whatever i have drawn is wrong for both qns.. thanks a lot experts!
First, please confirm or correct my guess as to which of the lines in the picture you had added. If confirming, please explain the basis on which you drew these lines.bomberkid said:thanks so much for your input haruspex..but pardon me, i still can't grasp how should i draw it..should i be drawing the image of the light in the mirror? if my light ray coming from the torch is reflected in the mirror, should i be drawing an angle of incident and reflection at a normal to the mirror? really confused
Ok, that makes it clearer, but as I wrote in post #2 some of your lines do make sense and are useful. I'm asking you to explain why you drew those lines. This will help me lead you to the answer.bomberkid said:hihi, sorry for the confusion, this is my test paper, all the lines drawn are wrong and just based on my guesswork, except for the normal. this is the original question, as attached. i have erased all the lines that were drawn wrongly, except for the normal at the plane mirror. that's the only thing i have gotten right so far. hope this is clearer now!
The given light ray from the torch won't do those things, but forget that light ray for the moment. Think about the torch as merely an object for which there will be images. You appear to have identified where its image will be in the mirror, and your lines from there through the lens midpoint and focal point lead you to another image, right? So where they meet indicates the position of what, exactly?bomberkid said:Well I drew the lines thinking that the light ray got to pass through one of the focal length, and another through the center of the lens. But that's totally wrong, the examiner totally marked it wrong.. So I don't think its correct. Maybe u can show me.what is the right drawing?
Or maybe because having arrows on them made the examiner think they were supposed to be part of the path of the light ray, not merely construction lines.BvU said:Add the right red cross because the arrows on those lines point in the wrong direction ?
We seem to be back to your first picture, almost, and as I posted then, it is mostly correct. The one wrong line is the lowest line from the mirror image. It's fine from there, through the mirror, as far as the lens, but there's no way it is going to pass through the lens in a straight line.bomberkid said:Is the drawing correct now?
When faced with a challenging light ray diagram question, it's important to break it down into smaller, more manageable parts. Start by identifying the key components of the diagram, such as the light source, objects, and mirrors or lenses. Then, use the rules of reflection and refraction to trace the paths of the light rays. It can also be helpful to draw multiple diagrams and consider different scenarios to find the correct solution.
The rules for drawing light ray diagrams depend on the type of diagram you are working with. For reflection, the angle of incidence is equal to the angle of reflection, and the incident ray, reflected ray, and normal line all lie in the same plane. For refraction, Snell's Law states that the ratio of the sines of the angles of incidence and refraction is equal to the ratio of the refractive indices of the two media. Keep in mind that light always travels in a straight line, and the shortest path between two points is taken.
The direction of light rays in a diagram can be determined using the rules of reflection and refraction. For reflection, the incident ray is drawn from the light source towards the object, and the reflected ray is drawn away from the object. For refraction, the incident ray is drawn towards the interface between two media, and the refracted ray is drawn away from the interface. Remember to always draw the rays as straight lines.
Light ray diagrams are used in science to visualize the behavior of light rays as they interact with objects, mirrors, and lenses. They help us understand the principles of reflection and refraction and how they affect the path of light. These diagrams are also helpful in predicting the behavior of light in different scenarios and can be used to design and optimize optical systems.
The best way to check if your light ray diagram is correct is to double-check that it follows the rules of reflection and refraction. Make sure that the angles of incidence and reflection are equal, and that Snell's Law is satisfied for refraction. You can also test your diagram by changing the angles or positions of objects in the diagram and seeing if the predicted outcome matches the actual outcome. Additionally, it can be helpful to consult with a teacher or classmate for feedback and validation.