All cameras form images in the same basic way.

The image formed in a camera is real.

The image formed in a camera is erect.

The image formed in a camera is generally enlarged.

In the camera, the diaphragm is placed in front of the convex lens.

The smaller the f-number of a camera, the wider the aperture is.

The shutter speed is expressed in metre per second.

The shutter speed is expressed in radian per second.

The shorter the exposure time, the lower the shutter speed is.

In a camera, the focusing ring is used to adjust the distance between the lens and the object.

The focusing ring is used to change the position of the lens in the camera.

In a camera, the position of the lens can be altered.

In a camera, the thickness of the lens can be altered.

In a camera, the focal length of the lens can be altered.

The cornea is transparent.

The aqueous humour is a transparent liquid.

The vitreous humour is an opaque liquid.

The ciliary muscles are attached to the eyelens.

The ciliary muscles can vary the thickness of the eyelens.

The ciliary muscles can vary the focal length of the eyelens.

The ciliary muscles can vary the power of the eyelens.

The ciliary muscles can vary the position of the eyelens.

The focal length of the eyelens can be altered.

The power of the eyelens can be altered.

The position of the eyelens can be altered.

The thickness of the eyelens can be altered.

The blind spot on the retina is used for viewing very small objects.

When objects at infinity are viewed, the eyes are relaxed.

Objects at infinity can be viewed conveniently for a long time.

When the compound microscope is used, the object should be placed between Fo and 2Fo, where Fo is the focus of the objective.

The image formed by the objective of the compound microscope is real.

The image formed by the objective of the compound microscope is enlarged.

The image formed by the eyepiece of the compound microscope is erect with respect to its object.

The image formed by the eyepiece of the compound microscope is larger than its object.

The separation of the lenses in a compound microscope is the sum of the image distance of the objective and the objective distance of the eyepiece.

Compound microscopes are used to study living cells and for regular use when magnification is enough.

Optical microscopes have a lower magnifying power than the electron microscope.

Electron microscopes deliver a more detailed image compared to optical microscopes.

The image formed by the objective of the compound microscope is real.

The image formed by the objective of the compound microscope is erect.

The image formed by the objective of the compound microscope is enlarged.

The image formed by the eyepiece of the compound microscope is real.

The image formed by the eyepiece of the compound microscope is erect with respect to its object.

The image formed by the eyepiece of the compound microscope is erect with respect to its object.

The image formed by the eyepiece of the compound microscope is larger than its object.

The image formed by the eyepiece of the compound microscope is larger than the first object.

The final image formed by the compound microscope can be seen clearly when the eye is very close to the objective.

The magnifying power of a compound microscope is the product of the magnification of the objective and the magnification of the eyepiece.

The magnifying power of a compound microscope is the sum of the magnification of the objective and the magnifying power of the eyepiece

The separation of the lenses in a compound microscope is the sum of the image distance of the objective and the objective distance of the eyepiece.

For a large magnifying power of a compound microscope both the objective and the eyepiece must have long focal lengths.

In a compound microscope, the focal length of the objective must be larger than that of the eyepiece.

As the magnifying power increases, the sharpness of images is reduced.

Compound microscopes are used to study living cells and for regular use when magnification is enough.

Optical microscopes have a lower magnifying power than the electron microscope.

Electron microscopes deliver a more detailed image compared to optical microscopes.

The wavelengths of electron waves are longer than those of light.

The refracting astronomical telescope consists of an objective of short focal length.

The refracting astronomical telescope consists of an eyepiece of long focal length.

In the refracting astronomical telescope, the eyepiece is a concave lens.

In the refracting astronomical telescope, the focal length of the objective is larger than that of the eyepiece.

In the refracting astronomical telescope, the power of the objective is larger than that of the eyepiece.

In the refracting astronomical telescope, the image formed by the objective is real.

In the refracting astronomical telescope, the image formed by the objective is erect.

In the refracting astronomical telescope, the image formed by the objective is at the focus of the objective.

In the refracting astronomical telescope, the final image is formed by the eyepiece.

In the refracting astronomical telescope, the final image formed is real.

In the refracting astronomical telescope, the final image formed is enlarge.

In the refracting astronomical telescope, the final image formed is erect with respect to the distant object.

In the refracting astronomical telescope, the final image formed is erect with respect to the first image.

The magnifying power of the refracting astronomical telescope is equal to the ratio of the image distance of the objective to the object distance of the eyepiece.

For normal adjustment of the refracting astronomical telescope, the magnifying power is the ratio of the focal length of the objective to the focal length of the eyepiece.

The separation of the lenses of the refracting astronomical telescope is the sum of the image distance of the objective and the object distance of the eyepiece.

For normal adjustment of the refracting astronomical telescope, the separation of the lenses is the sum of the focal length of the objective and the focal length of the eyepiece.

For a high magnifying power of the refracting astronomical telescope, an objective of long focal length and an eyepiece of short focal length are required.

In practice, it is easy to make a perfect convex lens of large diameter free from defects.

The final image formed by the astronomical telescope is erect.

In the terrestrial telescope, the objective is a concave lens.

The final image formed by a terrestrial telescope is erect.

The terrestrial telescope with a concave lens as an eyepiece is very long.

Binoculars are widely used as astronomical telescopes.

A microscope is a real-world instrument employing light.

Light and optics provide various applications in our daily life.

The reflection of light is applied in mirrors.

The refraction of light is applied in lenses.

There is visible laser.

There is invisible laser.

There is infrared laser.

There is ultraviolet laser.

Laser beam is monochromatic.

Laser beam is coherent.

Laser is composed of electromagnetic waves.

The laser medium must be a gas.

The laser medium must not be a liquid.

The laser medium may be a semiconductor crystal.

The laser medium may be a crystalline solid.

To sustain a laser action the lower level must be depopulated while the upper level is populated.

The output lasers beam is wide.

The output lasers emission is coherent.

A modest laser power can produce a high intensity inside the small area of laser beam.

A 1 mW He-Ne laser beam is much brighter than the sunlight.

One of the unique properties of a laser beam is coherence.

The light waves a laser beam contains are in phase with one another.

Lasers are used in the semiconductor industries for photolithography.

Lasers are used in computer printers.

Lasers are used to store and retrieve information in compact disc (CD).

A fibre optic cable can contain a varying number of glass fibres.

The core and cladding of the optical fibre have different refractive indices.

In an optical fibre, the refractive index of the core is slightly smaller than that of the cladding.

If the angle of incidence at the core to the cladding interface is less than the critical angle, only refraction will take place.

If the angle of incidence at the core to the cladding interface is less than the critical angle, the light beam attenuates and dies off over a certain distance.

A useful application of fibre optics is in endoscopy.

The endoscopy is a non-surgical procedure.

In a spectrophotometer, dispersion element separates light into spectrum.

The human eye cannot response the light of wavelength 300 nm.

The human eye cannot response the light of wavelength 500 nm.

The human eye cannot response the light of wavelength 750 nm.

Luminous intensity can be measured in lumen per steradian (lm/sr).

The smaller the f-number, the narrower the aperture is.

The shorter the exposure time, the smaller the shutter speed is.

The iris is in the centre of the pupil.

The focal length of the eye can be altered.

The focal length of the objective of compound microscope is shorter than that of the eyepiece.

Human eye is more sensitive to red light compared to other colors.