Microscopes and Magnification

When looking at a specimen on your slide, you should always start with the

• low objective lens
• medium objective lens
• high objective lens

A compound light microscope will use _______ or more lenses at the same time.

• 1
• 2
• 3

Magnifies the image (usually 10x) and you look into the scope here.

• Eyepiece/ Ocular
• arm
• low power objective
• fine adjustment

How many microns μm = 1 mm?

• 1,000

• 1,000,000

• 10,000

• 100,000

To calculate magnification of an electron micrograph we use......

• magnification = image size x actual size

• magnification = image size ÷ actual size

• magnification = actual size ÷ field of view

• magnification = ocular lens x objective lens

To calculate the image size of an electron micrograph if we use.....

• Image size = Actual size x Magnification

• Image size = Magnification ÷ Actual size

• Image size = Actual size ÷ magnification

• Image size = Magnification x Actual size

Josie measured the scale bar image to be 80 mm. What is the Magnification of this electron micrograph?

I = AM

• 160X

• 0.00625 X

• 0.16X

• 25,000X

If the scale bar measures 60 mm and the actual size it represents is 30 μm , what is the magnification?

• 2,000X

• 150X

• 5,000X

• 20X

If a scale bar measures 32 mm and it states it's length is 100 μm, what is the magnification?

• 320 x

• 3,200 x

• 0.32 x

• 32,000 x

If a bacteria image measures 450 mm and the magnification is 15,000x, what is the actual size of the bacteria?

• 30 µm
• 0.3 µm
• 300 µm
• 3,000 µm