3.2.4 Density of Irregular Objects

• The mass measurement is used later to calculate the density of the irregular object.
• Water is used in this experiment for volume displacement.
• Density is calculated using the formula: Density = Mass / Volume.
• In this experiment, water serves as the medium for measuring volume displacement
• If the scale reads 50 grams, the mass of the object is 50 grams.
• What is the formula for density?

  Density = Mass/Volume
• The calculated density can be compared to known densities of common materials to identify the object's composition
• What is the purpose of a measuring cylinder filled with water in this experiment?

  Volume displacement
• Match the material with its purpose in the experiment:

  Irregular object ↔️ Density measurement

  Measuring cylinder ↔️ Volume displacement

  Measuring scale ↔️ Mass measurement
• Steps to determine the volume of an irregular object using water displacement

  1️⃣ Fill the measuring cylinder partially with water and note the initial volume

  2️⃣ Tie the object to a piece of string and lower it into the water

  3️⃣ Note the final volume after the object is fully submerged

  4️⃣ Calculate the volume of the object by subtracting the initial volume from the final volume
• What is the density of an object with a mass of 100 grams and a volume of 50 cm³?

  2 g/cm³
• The measuring scale is used to measure the mass of the object.
• What should you note first when determining volume using water displacement?

  Initial water volume
• Match the quantity with its formula:

  Density ↔️ $ρ =$$m / V$

  Mass ↔️ m

  Volume ↔️ V
• If an object's density is around 0.5 g/cm³, it is likely made of wood.
• Steps to measure the mass of an irregular object using a scale

  1️⃣ Place the object on the measuring scale

  2️⃣ Record the mass displayed on the scale
• A clamp is used to secure the measuring cylinder
• The volume of the object is calculated by subtracting the initial volume from the final volume.
• What is the measuring cylinder used for in this experiment?

  Volume displacement
• Steps to measure the mass of an irregular object using a scale

  1️⃣ Place the object on the measuring scale

  2️⃣ Record the mass displayed
• The volume of the irregular object is equal to the difference between the final and initial water levels.
• What are the units for mass, volume, and density in this experiment?

  g, cm³, g/cm³
• A calculator is needed to calculate the density
• Why is a measuring cylinder used in this experiment?

  For volume displacement
• What is the initial volume of water in the measuring cylinder in the example provided?

  50 cm³
• Match the material with its purpose:

  Measuring cylinder ↔️ Volume measurement

  Measuring scale ↔️ Mass measurement

  String ↔️ Object suspension

  Clamp ↔️ Securing measuring cylinder
• What is the purpose of the string in this experiment?

  Suspend the object
• The volume of the object is calculated by subtracting the initial volume from the final
• If an object has a mass of 200 grams and a volume of 100 cm³, its density is 2 g/cm³.