The image shows two graduated cylinders used to measure the volume of a liquid and determine the volume of a solid object using the
water displacement method.
Let’s analyze each part:
---
Left Cylinder:
- The liquid level is at
60 mL.
- An eye is shown at the same level as the meniscus (the curved surface of the liquid), indicating
correct reading technique — viewing at eye level to avoid parallax error.
- This is the
initial volume of water before adding the object.
---
Right Cylinder:
- A solid object is submerged in the water.
- The water level has risen to
80 mL.
- The eye is shown at the correct level (eye level with the meniscus) for accurate reading.
- This is the
final volume after the object is added.
---
Objective:
To find the
volume of the solid object, we use the
principle of water displacement:
> Volume of object = Final volume – Initial volume
So,
$$
\text{Volume} = 80\, \text{mL} - 60\, \text{mL} = 20\, \text{mL}
$$
Since 1 mL = 1 cm³, the volume of the object is
20 cm³.
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✔ Answer:
The volume of the solid object is
20 mL (or 20 cm³).
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🔍 Explanation:
- The water displacement method works because when an object is fully submerged, it displaces a volume of water equal to its own volume.
- The rise in water level reflects this displaced volume.
- Proper eye alignment ensures accuracy — looking straight at the meniscus avoids errors due to viewing angle.
This is a classic lab technique used in physics and chemistry to measure the volume of irregularly shaped objects.
Parent Tip: Review the logic above to help your child master the concept of volume of irregular solids worksheet.
