Lesson 5: Properties of Matter II


Activity 1: Volume, Mass, and Weight

Materials: 250-ml beaker (kit), 3 irregularly shaped objects (such as small toys), calculator, dynamometer (kit), large transparent container (such as a two-liter bottle with the top cut off), permanent marker, ruler, wooden cube (kit)
In today's lessons, you will be challenged to further develop your understanding of some of the properties of matter. In this activity, you will be finding the volume of both regular and irregular three-dimensional shapes. For regular shapes — cubes, rectangular prisms, spheres, and pyramids — you will use specific formulas to find volume. For irregular shapes, you will use a procedure called the displacement method to find volume. Remember that the formula for volume is a measure of the length x width x height of an object. This formula may vary some depending on the object, so be sure you consider the object before calculating its volume.

Volume of Regular Shapes

To find the formula for three-dimensional regular shapes, you will use the formulas listed on the "Three-Dimensional Shapes" graphic. Also note the following:
  • Three-dimensional squares are called cubes, and rectangular objects are called rectangular prisms.
  • Three-dimensional circular objects are spheres. Note that the measurement of pi (3.14) in the formula is a constant that represents a relationship between the distance around a circle (circumference) and the circle's diameter.
  • Three-dimensional triangles are pyramids. In the formula, B is the base of the pyramid and is equal to the length x width of the bottom. The letter "h" represents the height of the pyramid.
Three-Dimensional Shapes
Using the formulas provided, solve the problems on the "Volume of Regular Shapes" activity page.
Use the following answer key to check your child's answers.
Volume of Regular Shapes Answer Key

Volume of Irregular Shapes

Not all objects have a regular shape; some have an irregular shape, and finding their volume can be challenging. One way to find the volume of an irregular shape is through the displacement method. This method involves putting an object in water and measuring how much the water level rises. In this part of the activity, you will use a very basic form of the displacement method.

First, gather your materials. You will need a transparent container (such as a 2-liter bottle with its top cut off), a marker, a ruler, an object that is a cube or rectangular prism (such as a small block of wood), a 250-ml beaker, and 3 irregularly shaped objects (such as small toys). You will record your measurements on the top section of the "Volume, Mass, and Weight" activity page.

Next, follow these steps:
  1. Pour water into a transparent container. The container should be only 1/2 to 2/3 full. (You need enough water to be able to submerge your objects; if there if too much water, the water may overflow the container.)
  2. Mark the water level in the container with a marker.
  3. Use a ruler to find the length, width, and height of your cube (or rectangular prism). Record the object's volume in cubic centimeters.
  4. Now place the cube in the container until it sinks or is completely submerged. If the object does not sink, use a pencil or other small object to push the object under the water completely. The object does not have to touch the bottom, but you will want to make sure that it is completely covered by water.
  5. Use your marker to mark where the water line is now.
  6. Keep the object in water as you carefully pour water from the container into your 250-ml beaker. Keep pouring out water until the water level is at the original (bottom) line.
  7. Write down the amount of water in your beaker. This should be in milliliters.
  8. Convert milliliters to cubic centimeters (cm3). (Example: 200 milliliters = 200 cubic centimeters; 127 milliliters = 127 cubic centimeters)
  9. This number should be close to the number you calculated in Step 3. It will not be exact but should be fairly close (within 5-10 milliliters).
  10. Pour the water from the beaker back into your container.
  11. Make sure the water is at the original line. If not, add water as needed.
  12. Repeat the displacement method for each of your three irregularly shaped objects and record their volumes on the activity page.
In the next part of the activity, you will determine how much each of your 4 objects would weigh on Earth and on other locations in the solar system.

Mass is the amount of matter in an object, and weight is the measure of the heaviness of an object as a result of the influence of gravity. To help demonstrate this difference, you will find the weight of your four objects based on where the objects are located. First you will find each objects' weight on Earth and then determine what the objects would weigh on the Moon, Sun, Mars, and Jupiter.

Follow these steps and then record your data on bottom section of the "Volume, Mass, and Weight" activity page:
  1. Using a dynamometer, measure the weight of your regular object and record its weight (in grams) in the Earth column of the table.
  2. Repeat Step 1 for each of the three irregular objects.
  3. Use the following information to calculate the weight of each object on other solar bodies (and record the weight for each object in the appropriate column):
    • Moon: weight is 16.7% of weight on Earth
    • Mars: weight is 37% of weight on Earth
    • Jupiter: weight is 236% of weight on Earth
    • Sun: weight is 2700% of weight on Earth
Volume, Mass, and Weight Answer Key