Question

In biology class, Vijay learns the width of a human hair is about a million times larger than the width of an atom. An atom's width ranges from
1
×
10
−
10
to
5
×
10
−
10
meter. Which of these statements are true? Choose all that are correct.

A.
A human hair could have a width of
3
×
10
−
4
meter.

B.
A particle bigger than an atom by a factor of
1
×
10
4
could have a width
4
×
10
−
14
meter.

C.
Ten billion (10,000,000,000) atoms of the smallest possible width lined up in a row is 1 meter in length.

D.
The maximum width of an atom is 4 times more than the minimum width.

E.
An object that is 0.000000000002 meter in width is 100 times smaller than the width of an atom that is
2
×
10
−
10
meter.

Answer 1

Correct answers: A, C, and E.

Explanations:
- A: True. A hair ≈ 10^6 times an atom: 10^6 × (1×10^-10 to 5×10^-10) = 1×10^-4 to 5×10^-4 m, and 3×10^-4 m lies in that range.
- B: False. A particle 10^4 times an atom would be ~10^4 × (1×10^-10) = 1×10^-6 m or larger; 4×10^-14 m is far smaller than an atom.
- C: True. 10,000,000,000 × 1×10^-10 m = 1 m.
- D: False. max/min = (5×10^-10)/(1×10^-10) = 5, so the maximum is 5 times the minimum (not 4 times).
- E: True. 0.000000000002 m = 2×10^-12 m, and (2×10^-10)/(2×10^-12) = 100, so it is 100 times smaller.