Simple Microscope Angular Magnification
What are three characteristics of laser?
In a compound microscope magnification will be large, if the focal length of the eye piece is
Equal to that of objective
Less than that of objective
When image is formed at infinity, what does it mean??
What we'll see?
An object is put at a distance 25 cm from the optical centre of a convex lens. If it's real image is formed at a distance 30 cm from the lens to its focal length is about
(1) 10 cm
(2) 14 cm
(3) 12 cm
(4) 20 cm
What is the full form of VDU in computer
A nearsighted man can clearly see objects up to a distance of 2m. Calculate the power of the lens of the spectacles necessary for the remedy of this defect.
- 1 keV
- 25 keV
- 500 keV
- 100 keV
- 6, 6
- 9, 6
- 6, 9
- 9, 9
State the differences between a convex and a concave lens.
- 12 cm
- 24 cm
- 36 cm
- 48 cm
The magnifying power of a compound microscope increases when
The focal length of the objective lens is increased and that of the eyepiece is decreased
The focal length of the eyepiece is increased and that of the objective lens is decreased.
Focal lengths of both objective and eyepiece are increased.
Focal length of both objective and eyepiece are decreased.
A person uses a lens of power +3D to normalize vision. Find the near point of the hypermetropic eye (in m).
If u aan v are the objobj and image distances respectively due to convex lens then which among the following statements is false
(1)as u increases, v also increases
(2)as u increases, v decreases
(3) as u increases v remare constant
(4)None of the above
A simple magnifying glass consists of a
convex lens of large focal length
convex lens of small focal length
plane mirror only
How should people wearing spectacles work with a microscope?
They should keep on wearing their spectacles.
They should never use the microscope.
They should take off their spectacles.
They may either put on their spectacles or they may take off their spectacles.
- Higher focal length
Smaller focal length
A child has near point at 10 cm. What is the maximum angular magnification the child can have with a convex lens of focal length 10 cm?
- 37.3 cm
- 46.0 cm
- 50.0 cm
- 53.4 cm
Consider a beam expander which consists of two converging lenses of focal lengths and having a common optical axis. A laser beam of diameter is incident on the focal length lens. Then what is the diameter (in mm) of the final beam (see figure)?
Magnifying power of a simple microscope is (when final image is formed at D = 25 cm from eye)
[MP PET 1996; BVP 2003]
Lenses are used to form images by reflection in optical instruments.