How do you find the density of an object (6th grade)?

To find the density of an object, you need to know two things: its mass and its volume. Density is simply how much "stuff" (mass) is packed into a certain amount of space (volume).

Here's how you do it:

1. Find the Mass: Mass is how much matter is in an object. You can measure mass using a balance or a scale. The mass is usually measured in grams (g) or kilograms (kg).

2. Find the Volume: Volume is the amount of space an object takes up. How you find the volume depends on the shape of the object:

   • Regularly Shaped Objects (like a box): Measure the length, width, and height of the object using a ruler. Then multiply them together: Volume = Length x Width x Height. The volume will be in cubic centimeters (cm³) or cubic meters (m³).
   • Irregularly Shaped Objects (like a rock): Use the water displacement method.
     1. Fill a graduated cylinder (a tall, clear container with markings for measuring volume) with a known amount of water.
     2. Carefully place the object in the water.
     3. The water level will rise. Subtract the original water level from the new water level. The difference is the volume of the object. This will be in milliliters (mL), and 1 mL is equal to 1 cm³.

3. Calculate the Density: Density is calculated using the following formula:

   Density = Mass / Volume

   You can remember this formula using a trick! Draw a heart. Write Mass at the top point of the heart and Volume at the bottom. This shows you Mass over Volume (M/V).

4. Units: The unit for density is usually grams per cubic centimeter (g/cm³) or kilograms per cubic meter (kg/m³).

Example:

Let's say you have a small rock.

• You measure its mass and find it to be 60 grams.
• You use the water displacement method and find its volume to be 20 cm³.

To find the density, you would divide the mass (60 g) by the volume (20 cm³):

Density = 60 g / 20 cm³ = 3 g/cm³

So, the density of the rock is 3 grams per cubic centimeter.