Scalar quantities

• What are the two categories of physical quantities measured by scientists?

  Scalars and vectors
• How are scalar and vector quantities treated in calculations?

  They are treated differently
• What is a scalar quantity?

  • A physical quantity that has only magnitude
  • Examples include:
  • Temperature (e.g., 10°C)
  • Mass (e.g., 5 kg)
  • Energy (e.g., 2,000 J)
  • Distance (e.g., 19 m)
  • Speed (e.g., 8 m/s)
  • Density (e.g., 1,500 kg/m³)
• What does the term 'magnitude' refer to in the context of scalar quantities?

  It refers to the size of a physical quantity
• How do you calculate the total mass of a climber carrying a backpack?

  Add the mass of the climber to the mass of the backpack
• What is the total mass of a 75 kg climber carrying a 15 kg backpack?

  90 kg
• How can scalar quantities be subtracted?

  By subtracting one value from another
• If a room is heated from 12°C to 21°C, what is the increase in temperature?

  9°C
• What are the steps to add scalar quantities?

  1. Identify the scalar quantities to be added
  2. Add their values together
  3. The result is the sum of the scalar quantities
• What are the steps to subtract scalar quantities?

  1. Identify the scalar quantities to be subtracted
  2. Subtract one value from another
  3. The result is the difference between the scalar quantities
• What is an example of a scalar quantity related to temperature?

  10 degrees Celsius (°C)
• What is an example of a scalar quantity related to mass?

  5 kilograms (kg)
• What is an example of a scalar quantity related to energy?

  2,000 joules (J)
• What is an example of a scalar quantity related to distance?

  19 metres (m)
• What is an example of a scalar quantity related to speed?

  8 metres per second (m/s)
• What is an example of a scalar quantity related to density?

  1,500 kilograms per metre cubed (kg/m³)
• What is the significance of scalar quantities in scientific measurements?

  • They provide essential data for calculations
  • They are easier to manipulate mathematically
  • They represent measurable aspects of physical phenomena