#$&*
Phy 121
Your 'question form' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
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Chapter 1 Problem 18
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I am unsure as to how to do problem 18 in chapter 1. It asks what is an atoms diameter in inches. Here is what I did:
1 x 10^-10 m * 3.28 ft / 1 m = 39.36 x 10^-10 inches.
@& Your calculation isn't complete.
1 x 10^-10 m * 3.28 ft / 1 m = 3.28 * 10^-10 ft.
You left out a step, but got the correct result:
1 x 10^-10 m * 3.28 ft / 1 m * 12 inches / ft = 39.36 x 10^-10 inches.*@
The next portion asks how many atoms would fit across 1 cm. Here, I really do not know what 1 x 10^-10 is. I understand its a very small measurement, but I do not know how to divide 1 cm by it and get any real number.
Aside from just this 1 cm / 1 x 10^-10/100 cm
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@& 10^-10 means 1 / 10^10 = 1 / ( 10 * 10 * 10 * 10 * 10 * 10 * 10 * 10 * 10 * 10) = 1 / 10 000 000 000 or .0000000001.
Your instinct 1 cm / (1 * 10^-10) is correct, but your denominator doesn't have units, and you're going to need to express these quantities in common units.
There are 100 cm in a meter, so 1 cm is .01 meter or 10^-2 meter.
So the calculation is
1 cm / (1 * 10^-10 meter)
= 10^-2 meter / (10^-10 meter)
= 10^8.
Review the laws of exponents if you don't understand why 10^-2 / 10^-10 is 10^8.
This result tells you that 10^8 atoms would fit across a centimeter.
That's 100 000 000 atoms.*@