What is density and why should I care?

Density is a measure of the amount of matter an object has in a specific space. It is calculated by dividing the mass of the object by the volume of the object. Knowing the density of an object can help you understand what the object is composed of, how big it is, and how heavy it is. Knowing the density is also important in determining the temperature and pressure of the object.

Significant Digits and Density Calculations

When performing calculations involving density, it is important to be aware of significant digits. Significant digits are the digits that are known to be exact and are used to represent the precision of a measurement. A good rule of thumb is that all non-zero digits are significant and any zeros between non-zero numbers are also significant. For example, the number 13.04 has four significant digits, while the number 0.0045 has three significant digits.

How to Calculate Density with Significant Digits

When calculating the density of an object, the first step is to identify the mass and the volume of the object. Once you have these measurements, you can then use the formula D=m/V to calculate the density of the object. The result of this calculation should be rounded to the number of significant digits identified in the measurements.

Example:

Let's say you have a block of wood with a mass of 28.42 g and a volume of 2.40 cm³. To calculate the density of the wood, you would use the formula D=m/V. Plugging in the measurements, you get D= 28.42g/2.40 cm³ = 11.84 g/cm³. Because both measurements have three significant digits, you should round the result to three significant digits, giving you a final answer of 11.8 g/cm³.

Conclusion

Density calculations with significant digits can be a tricky subject, but it's important to understand the concept in order to accurately calculate the density of an object. By following the formula D=m/V and rounding the result to the number of significant digits of the measurements, you can properly determine the density of an object.

Density Calculations With Significant Digits Worksheet Answers