Multiple websites provide this info (together with illustration)
May be you can have a look once...are these illustration totally wrong ?
https://www.premiumbeat.com/blog/understanding-lenses-what-is-focal-length/
I clearly need to study on this but I think some "physics experts" also might need to learn to understand simple question and answer then straight foreward. Otherwise general public will always be confused by simple maths and physicist will only know numbers and not the real life situations...
It is a very simple question without any in depth explanation.
Could you please say why some photography websites mention focal length as distance from point of convergence to the sensor.
On the attached image. Is both the definition correct?
First of all, Let me present some of the things I found from research. (considering convex lens)
Interpretation 1 => Focal length
is the distance from the center of the lens to the point where all rays converge.
Interpretation2 => Focal length
is the distance from the point of convergence to...
COOOOOOL...thanks MODs. This is interesting. I don't understand intuitively but I believe it from the formulae...
Can I ask you for a favor? I am engineering student...but I sooo want to understand relativity...
Would you recommend me some books, article,(website/blogs/archive) to get to...
Some more details would be nice. I am not hard core physics kid but interested a lot.
So, let's get it this way. It works on earth, if two bodies travel at 5m/s. One would see the other @ speed of 10m/s.
When or at what speed this classical concept stops working and relativity takes over ?
How...
My understanding:
Relative to stationary body, the speed of light is 3*10^8[m/s]
In all intertial frame of reference the speed of light remains constant:
menaing, if I travel in rocketship @ 0.5*c, the light coming out of my rocketship will also travel at 3*10^8[m/s]. The law of physics remains...
Thank you all for your thoughts and time. I might not have the exact answer but it is beautiful to see everybody from globe try and help each other. Learned interesting stuffs in the meanwhile. Thanks!
So, basically the process of finding(or at least assuming the image is from past) is:
1. Find the distance of the object.
2. Observe the image of the same object
Either 1 or 2 could be first step.
3. Then say how old the image is based on distance and speed of light?
I got it. Yes.
I know we see thing when the image if them fall on our eye.
Ok everyone seem to explain thing but not answer my real thing. My question is more about measurement than the principle. How do we measure two objects observing the light they emit? That is my real question.
Thanks for your responses. I think it will be clear if someone could answer this question.If there is another sun
At distance two times from the present sun.
How do we manipulate light coming from them to see one is 8 mins away and the other is 16mins??
I understand all of your explanation. But again, if the light has to come to our retina, what is the meaning of looking further. For me it seems like there is no looking further. Just wait for the light to come to you and if it took 300000... Years to come to you it is that many years old. How...
I understand the basic analogy of looking at things from the past. Let me explain what I know before I ask about what I want to know.
The sun is 8 min light speed away. So whatever we see is the 8 min ago sun.
Similarly, If we see the star 1 light year far...we can say we are looking at...