If the angle is either 0 or 180, that means that there is either negative or positive work, so A and D are not correct.
If the angle is 45, then there is still some work involved.
The only option where there is no work done by a force is B. when the angle is between the force and displacement is 90.
If the potassium atoms could be lined up in a row, it would take to make a 1.00 ft row of potassium atoms is 5.45 × 10⁻⁸.
Potassium atom is represented by K with atomic number 19. It is a silvery white metal.
Given,
Radius = 280pm = 280 × 10⁻¹²m
Diameter = 2radius = 560× 10⁻¹²m = 560pm
We know that,
1 feet = 0.305m
So, number of potassium atoms that fits into the row,
1 feet = 0.305/560 × 10⁻¹²
1 feet = 5.45 × 10⁻⁸
Hence, it takes 5.45 × 10⁻⁸ atoms of potassium to make a 1 feet row.
Learn more about Potassium here, brainly.com/question/13321031
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