How do you find the volume of a irregular object?
Answers
Find the Volume of an Irregular Object Using a Graduated Cylinder
Finding the volume of a regular object, such as cube or sphere, is typically done using an equation. Irregular objects like a screw or rock require a more hands on approach. Luckily, there is a straightforward way to calculate the volume of irregular objects using the water levels in a graduated cylinder.
Part One of Three:
Reading the Initial Water Level
Find the Volume of an Irregular Object Using a Graduated Cylinder Step 1
1
Add water to a graduated cylinder. Choose a graduated cylinder that the object will easily fit inside. Tilt the cylinder while pouring the water to reduce bubbles. Pour enough water in to fill the cylinder to the halfway mark.[1]
Cylinder Step 2
2
Read the meniscus. You will notice that the water is higher on the sides of the cylinder and droops slightly in the middle. This droop is known as the meniscus and is the standard point at which the water level is measured. Make sure that the cylinder is on a flat, level surface and that there are no bubbles. Look closely where the meniscus rests. Step 3
3
Record your measurement. It will be important to know the initial water level exactly. Write down the measurement that you took in a table or lab notebook. Your measurement will be mL. [3]
Part Two of Three:
Measuring the Final Water
Cylinder Step 4
1
Submerge your object. Tilt the cylinder. Slide the object into the water slightly. Be sure that your object is completely submerged in the water. If there is not enough water to submerge the object, you will have to start over with more water in the cylinder.[4]
Cylinder Step 5
2
Take a new measurement. Let the object and the water settle. Make sure that the cylinder is on a flat level surface. Now look at the water level (again read the meniscus). The water level should have increased with the object being added to the cylinder
Step 6
3
Record your final measurement. The final measurement will be just as important as the initial measurement in your calculations. It too must be precise. Write down the final water level in mL in your table or lab
Volume of an Irregular Object Using a Graduated Cylinder Step 7
1
Understand the measurements. Some people jump to the conclusion that the final reading gives them the volume of their object, but this is incorrect. The final reading is the volume of water plus the volume of your object. You will need to find the difference of the final and initial readings to know the volume of your object.[7]
Step 8
2
Solve for the difference between water levels. You will set up the equation Vtotal - Vwater = Vobject. Vtotal is your final measurement, Vwater is your initial measurement, and Vobject is the volume of your object. In other words, subtract the first measurement from the second to find the volume of your object.[8]
Step 9
3
Analyze your answer. Make sure that the volume you calculate makes sense. Obviously, you can check your calculation with a calculator. Some obvious signs of a mistake are things like your object having negative volume (this isn’t possible) or a volume larger than the cylinder could hold (a volume of 30 mL cannot be measured in a 25 mL cylinder). If your answer seems wrong, you should first check your equation to make sure you did the math properly. If you did, you will have to redo the experiment and obtain new measurements.[9]
If you found a negative volume, it is likely that you simply mixed up the initial and final measurements in your equation and do not need to redo the experiment.
If you obtain a number too large to be reasonable, you either made an arithmetic error or wrote down incorrect measurements. If it is the latter, you will have to redo the experiment.
Answer:
To measure the volume of an irregular solid, pour water in a graduated cylinder, read the water volume, immerse the object in the cylinder, and subtract the initial water volume from the new volume to get the volume of the object. Use a graduated cylinder and water to accomplish this task.
Find the water volume
Measure enough water to cover the whole object, and pour it into a graduated cylinder, making sure you don't completely fill the cylinder. Read the volume of the water before displacement, and record the value.
Submerge the solid into the water
Immerse the solid into the cylinder so that the water completely covers the solid without any spillage. Let the water settle to avoid inaccurate reading. Read the new volume after displacement, and record the value. If necessary, repeat the process to ensure your values are accurate.
Calculate the volume of the solid
To find the volume of the solid, subtract the water volume before immersion from the new water volume after the immersion. For example, if the initial water volume in the cylinder is 10 cubic meters and the volume after immersion is 15 cubic meters, the volume of the irregular solid is 5 cubic meters.