"Published in Vacaville, California, USA"
When an irregular-shaped rock is placed in a cylindrical vessel of water whose radius is 4.18 in., the water rises 6.85 in. What is the volume of the rock if it is completely submerged?
Solution:
To illustrate the problem, it is better to draw the figure as follows
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| Photo by Math Principles in Everyday Life |
If you have an object with irregular shape, let's say a stone, for example, then it is difficult to get its volume. In this case, the only way to get the volume of an object is by immersion method. You will need a right circular cylinder with water and measure its height. Next, immerse an object in water in a right circular cylinder and measure its height. The difference of their height will be used to calculate the change of the volume of water which is equal to the volume of an object.
Since the change of the level of water in a right circular cylinder is given in the problem, therefore, the volume of an object is
