• About how much longer is the diameter of a grain of salt than the width of a human hair Grain of Salt (diameter) 3x10^-4 Human Hair (width) 8x10^-5

3 answers

To compare the diameter of a grain of salt to the width of a human hair, we need to divide the diameter of the grain of salt by the width of the human hair.

Given:

  • Diameter of a grain of salt = \(3 \times 10^{-4}\) meters
  • Width of a human hair = \(8 \times 10^{-5}\) meters

Now, we can calculate the ratio:

\[ \text{Ratio} = \frac{\text{Diameter of grain of salt}}{\text{Width of human hair}} = \frac{3 \times 10^{-4}}{8 \times 10^{-5}} \]

To simplify this, we can calculate it as follows:

\[ \frac{3}{8} \times \frac{10^{-4}}{10^{-5}} = \frac{3}{8} \times 10^{1} = \frac{3}{8} \times 10 = \frac{30}{8} = 3.75 \]

Thus, the diameter of a grain of salt is about 3.75 times longer than the width of a human hair.

Explain

Certainly! Let's break down the comparison between the diameter of a grain of salt and the width of a human hair step-by-step.

  1. Understanding the Measurements:

    • The diameter of a grain of salt is given as \(3 \times 10^{-4}\) meters. This means it is 0.0003 meters, or 0.3 millimeters.
    • The width of a human hair is given as \(8 \times 10^{-5}\) meters. This translates to 0.00008 meters, or 0.08 millimeters.
  2. Setting Up the Ratio:

    • To find out how much longer the grain of salt's diameter is than the human hair's width, you can set up a ratio: \[ \text{Ratio} = \frac{\text{Diameter of grain of salt}}{\text{Width of human hair}} = \frac{3 \times 10^{-4}}{8 \times 10^{-5}} \]
  3. Dividing the Numbers:

    • When you divide the two measurements, you can handle the coefficients (the numbers in front) and the powers of ten separately.
    • First, divide the coefficients: \(3\) (from the grain of salt) divided by \(8\) (from the human hair) gives: \[ \frac{3}{8} = 0.375 \]
    • Next, divide the powers of ten: \(\frac{10^{-4}}{10^{-5}} = 10^{-4 - (-5)} = 10^{-4 + 5} = 10^{1}\), which is \(10\).
  4. Combining the Results:

    • Now you multiply the results together: \[ 0.375 \times 10 = 3.75 \]
  5. Conclusion:

    • This means that the diameter of a grain of salt is about 3.75 times larger than the width of a human hair.

So, in summary, by setting up the division of the two measurements, we calculated a ratio that shows that a grain of salt’s diameter is 3.75 times longer than a human hair’s width.