Lenses and its application | Baamboozle - Baamboozle

0%

0 0 0

Back Restart

Lenses marker's formula

1/f = (n - 1) [ 1/ R1 - 1/R2 ]

Binoculars use total reflecting prisms. Why?

Because of the successive total internal reflections prisms, the length of the telescope is greatly reduced.

In normal adjustment, the separation of lenses ; L =

v o + f e

What are four main photometric quantities?

luminous flux, luminous intensity, luminance and illuminance

In astronomical telescope, a concave mirror used as the -------- instead of a convex lens.

objective

Formula of magnifying power of compound microscope is

MP = vo / uo ( 1 + D/ f e )

What are the units of luminous intensity, solid angle, luminance and illuminance?

candela or lumen per steradian , steradian , candela per metre squared , lux

the front portion of the eye is covered by a tough, transparent membrane

cornea

What are two main types of electron microscope?

scanning electron microscope(SEM) and transmission electron microscope (TEM)

Myopia can be corrected by using spectacles with ------- lenses.

concave

Formula of the inverse square law of illuminance is

Ev = Iv cos theta / r2

The light sensitive area of the cells, at the back of the eye is ----

the retina

Sign convention , the heights below the principal axis are _____

negative or minus

A magnifying glass that has a bi-convex lens with a short focal length is a

simple microscope

A compound microscope has at least two convex lenses; an ---- lens and an ----- lens.

objective / eyepiece

For normal person, the least distance of distinct vision is

25 cm

Due to an eyeball is too short or due to the eye - lens cannot be sufficiently convex can be caused

farsightedness or hyperopia

The pupil automatically contracts in ------- light

bright

luminous flux is measured in --------

lumen (lm)

------- are attached to the eye lens.

The ciliary muscles

What are widely used as terrestrial telescopes?

binoculars

In compound microscope, a --------------- mounted beneath the slides can be adjusted to give reflected light to object.

concave mirror

Which lenses use in electron microscopes?

electrostatic or electromagnetic

The optical instrument can be used for viewing distant objects is called a -----

telescope

In normal adjustment, the final image is at ----

infinity

In astronomical telescope, the final image formed by the eyepiece is -------, ----- than the first image.

virtual / larger

In compound microscope, the objective lens produces an image which is -----, --- and ------ the size of the object.

real, inverted , larger than

Electron microscopes use electrons which have shorter wavelength that allow ---- magnification.

greater

In refracting astronomical telescope, to obtain sharp image of the distant objects the objective should have a ----- diameter.

large

two transparent liquids contains human eye are

aqueous humour and vitreous humour