Prove a lens must always be converging if

  • Thread starter Thread starter jones268
  • Start date Start date
  • Tags Tags
    Converging Lens
AI Thread Summary
A lens must be converging to produce an upright, enlarged image, as concave lenses only create virtual, reduced images. The discussion emphasizes the need for mathematical proof, suggesting that ray diagrams can visually demonstrate this principle. Converging lenses, such as convex lenses, are the only type capable of enlarging images while maintaining an upright orientation. Understanding the properties of lens types is crucial for solving this problem. Therefore, a converging lens is essential for achieving the desired image characteristics.
jones268
Messages
4
Reaction score
0
Prove a lens must always be converging if...

Consider a single lens with the object on the left side. Prove that for an upright, enlarged image that the lens must always be converging. I'm assuming my professor wants this to be mathematically proven, but I have no idea how to do so...HELP! I don't even know where to begin with this question
 
Physics news on Phys.org


Well, conceptually, a concave lens will ALWAYS produce an image that is virtual and reduced in size. So, if you want an enlarged image, your lens NEEDS to be converging - there are no other options.

You could prove this by drawing lens ray diagrams. If you haven't learned how to draw those, they're pretty simple! Here's something that might be helpful :
http://www.physicsclassroom.com/class/refrn/u14l5da.cfm
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top