Telescopes of the Galilean type are often used as opera glasses.
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The periodic arrangement of atoms in a crystal is called a lattice.
Forward bias is the condition that prevents current across the pn junction.
Which one is semiconductor in the following materials?
A. silicon
B. quartz
C. glass
D. copper
The basic quality of color was revealed by ________.
A. Isaac Newton
B. Olaf Römer
Christian Huygens
D. Planck
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