Optics Answers

Questions: 2 454

Answers by our Experts: 2 219

Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

Search & Filtering

A planoconvex lens is made of glass of refractive index 1.5. The radius of curvature of its spherical surface is 40 cm. At what distance from the lens will a parallel beam of light will get focussed? Draw a neat, clear labelled ray diagram to show image formation from the lens. What will be the nature and power of a combination of two such lenses kept with their (i) plane surfaces in contact (ii) spherical surfaces in contact.
We know light speed (average?) gets slow while in transparent materials like glass and water. And fraction of it gets absorbed as a heat (K.E. of molecules of glass). But my question is that How it can then leaving glass slab or any glass material comes to it's normal speed again? If light is absorbed in the material as heat then some light energy must be lost there, and after emanating from denser (glass) to back rare (air) where does this compensation of "speed" and energy comes from?
a double convex lens made up of a material of refractive index n1 is immersed in a liquid of n2, where n2>n1 . what changes would occur in nature of lens?
Find the distance at which an object should be placed in front of convex lens of focal length 10 cm to obtain an image of double its size
What was the original far point of a patient who had laser vision correction to reduce the minimum power of her eye by 4.25 diopters, producing normal distant vision for her? Assume a distance from the eye lens to the retina of 2.00 cm, so the minimum power for normal vision is 50.0 diopters.

Answer in cm
A fruit fly of height H sits in front of lens 1 on the central axis through the lens.The lens forms an image of the fly at a distance d = 30 cm from the fly; the image has the fly's orientation and height HI = 2.5 H. What are (a) the focal length f1 of the lens and (b) the object distance p1 of the fly? The fly then leaves lens 1 and sits in front of lens 2, which also forms an image at d = 30 cm that has the same orientation as the fly, but now HI = 0.86 H. What are (c) f2 and (d) p2?
A concave mirror has a radius of 20cm. An object is placed 30cm in front of the mirror. Determine where the image will appear
-4.5cm
-5.5cm
-6.5cm
-7.5cm
An object is placed in front of two convex lenses one by one at a distance ‘u’ from the lens .The focal lengths of lenses are 30cm and 15cm respectively.If the size of image formed in two cases is same,then ‘u’ is-
Why images formed by an object placed between two plane mirrors whose reflecting surfaces make an angle of 90° with one another lies on a circle?
A convex lens forms a real image of a point object at a distance of 50cm from convex lens.A concave lens is placed 10 cm behind the convex lens on the image side.On placing a plane mirror on the image side and facing cancave lens,it is observed that the final image now coincides with the object itself.The focal length of the concave lens is-