Transcript Microscope magnification ppt

Microscope
Magnification
Image
orientation
Depth of focus
Ocular lens (eyepiece) is 10X
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4x objective lens
10x objective lens
40x objective lens
100x objective lens
To get total magnification you multiply the
two together:
(10X) (4X) = 40X magnification
(10x) (10X) = 100X magnification
(10X) (40X) = 400X magnification
(10X) (100X) = 1000X magnification
Elodea Plant
40X
100X
Leaf on slide
400X
Cheek Cell
40X
100X
400X
How much bigger are the
items viewed under a
microscope?
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An average plant cell is 30
micrometers wide.
How big is that under:
– 4X objective?
– 10X objective?
– 40X objective?
– 100X objective?
Metric Conversions
Metric conversions
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Because items are magnified so greatly
under a microscope, it may not be
appropriate to use the same units to discuss
the size of something viewed with the naked
eye versus the size it appears under a
microscope.
Using the example from the previous slide,
an average plant cell is 30 micrometers in
diameter. What does the diameter appear to
be under a microscope using the 10X
objective? State your answer in centimeters.
Practice Question
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The lenses shown in the photo are
known as what?
A. projection lenses
B. eyepiece lenses
C. objective lenses
D. power lenses
Practice Question
All the lenses shown in the photo are
part of a structure of the microscope
known as the what?
A. rotating lenspiece
B. stage
C. revolving nosepiece
D. arm
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Practice Question
How is the total magnification of the
microscope is obtained?
A. multiplying the power of the objective lenses
together.
B. multiplying the power of the objective lens by
the power of the eyepiece lens.
C. dividing the power of the objective lens by the
power of the eyepiece lens.
D. dividing the power high power objective lens
by the power of the low power objective lens.
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Practice Question
What is best used as an adjustment on
a microscope to bring a specimen into
focus at high power?
A. Fine focus knob
B. Objective lens
C. Coarse focus knob
D. Eyepiece
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