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Genrish500 [490]
3 years ago
7

A focal arrangement that has a secondary mirror that reflects the focused light back through a hole in the primary mirror is a _

______________.
a. Cassegrain focus
b. Newtonian focus
c. Schmidt-Cassegrain focus
d. Schmidt focus
Biology
1 answer:
sveticcg [70]3 years ago
7 0
<span> a. Cassegrain focus</span> is the focal arrangement in a Cassegrain reflector used in optical telescopes and radio antennas. The primary mirror is a concave mirror, and the secondary mirror that reflects the focused light back to it is a convex mirror.
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Half life formula

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where:

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It is also possible to determine the remaining quantity of a substance using a few other parameters:

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Determine the initial amount of a substance. For example, N(0) = 2.5 kg.

Determine the final amount of a substance - for instance, N(t) = 2.1 kg.

Measure how long it took for that amount of material to decay. In our experiment, we observed that it took 5 minutes.

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If you are not certain that our calculator returned the correct result, you can always check it using the half life formula.

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