Wednesday, November 10, 2010

Measuring Volume of Water

1.0 Introduction

Volume is recognized as the measure how much certain object takes space. Volume is commonly used by many people as a term for describing liquids. However, it can also be used for other objects that have volume measured. Volume is measured by adding liquid to the graduated container and comparing the liquid level to the graduated scale. The measured volume corresponds to the volume of liquid contained in the graduated container.
When teaching measurement to students provide lots of opportunities for the students to order objects by size. Use everyday activities and real objects to help students understand measurement concepts. The terms non-standard and standard are often used when describing prescribed learning outcomes for measurement.
Measuring with non-standard units means measuring things with cups, spoon, glasses, jugs, etc. As long as the items used to measure with are all the same size, they are suitable to use.


2.0 Two Teaching Aids
2.1 Non-standard Measurement—Cup
         Cup is the non-standard measurement for volume of liquid. Cup is not a graduated container compare to graduated cylinder. We just can using cup to measure how many of cupfuls inside a container. We cannot measure the exactly volume of water in a container.


2.2 Standard Measurement—Graduated Cylinder
The graduated cylinder can use to measuring liquid volume. However, liquid volume is frequently measured using either a graduated cylinder or a buret. As the name implies, a graduated cylinder is a cylindrical glass or plastic tube sealed at one end with a calibrated scale etched or marked on the outside wall. Graduated cylinder comes in a range of sizes volume capacities, and much like a measuring cup. Graduated cylinder is a standard measurement for volume of liquid. This is suitable for high achiever students. Before learning about how to use these measuring instrument, teacher has to take note of the errors of parallax that might occur and about how to avoid them.
Two basic rules have to be considered for taking a correct reading from a measuring cylinder. First, your eye should be in line with the lower level of the surface of the water (meniscus) like B. Second, the measuring cylinder has to be placed on a level surface and not be tilted, as in the illustrated example!


3.0 Two Teaching Activities
3.1 Teaching With Non-standard Measurements

Learning outcome:
• To comparing capacity of a plastic bottle and a plastic bowl


Materials:
 • Set A: A plastic bottle and a cup
 • Set B: A pail and a cup

Procedures:
1. Divide the students into two groups which are low achiever students and high achiever
students. The low achiever students will name as Group A and the high achiever students
will name as Group B.
2. Group A will be given Set A and Group B will be given Set B. Ask the each group to  
    estimate each container can fill how many cupfuls of water.
3. Record the estimation number of cupfuls in the following table.
4. Give each group a set of containers.
5. Group A pours water into the plastic bottle until its top and Group B pours water into the 
    pail until its top.
6. Group A uses a cup to fill water from plastic bottle.
7. Record the number of cupfuls in the following table.
8. Group B uses a cup to fill water from pail.
9. Record the number of cupfuls in the following table.
           
Container
Estimation number of cupfuls
Measurement number of cupfuls
Plastic Bottle
(Group A)


Pail
(Group B)


       
   10. Ask Group A and Group B to complete the statements below.
                 

1. The plastic bottle can holds _________ cupfuls of water and the pail can  
     holds _______ cupfuls of water.
2. The water in the plastic bottle is ___________ than the pail.

Conclusion: Set A is most suitable for low achiever students because the container is small. So it is easy handle by them. While Set B is suitable for high achiever students because the container is easy handle by them, they can make the most accurate measurements.

    








3.2 Teaching With Standard Measurements

Learning outcome:
• To comparing capacity between graduated cylinders

Materials:
  • Plastic bowls
 • Graduated cylinders

Procedures:
1. Two basic rules have to let students know for taking a correct reading from a measuring  
    cylinder (as mention as above).
2. Divide the students into two groups which are low achiever students and high achiever
students. The low achiever students will name as Group A and the high achiever students
will name as Group B.
3. Each group will be given three set of containers.
4. Group A and Group B divided into 3 groups.
5. Each group need to fills in 1 liter, 2 liters and 3 liters of water in graduated cylinders by
    using plastic bowls.
6. Each group pours water into the graduated cylinder by using plastic bowl until its reach 1
    liter, 2 liters and 3 liters.
7. Teacher will check their measurement whether correct or not by using the two basic rules.
If the measurement is correct, teacher will put a tick. If wrong, teacher will put a cross.
For the wrong measurement, the group need to redo their measurement.

Measurement
1 liter
2 liters
3 liters
Group A



Group B




8. Ask Group A and Group B to complete the statements below.
                 

1. The water in a graduated cylinder which holds 1 liter of water is 
     __________ than the graduated cylinder which holds 2 liters of water.
2. The water in a graduated cylinder which holds 3 liters of water is 
     __________ than the graduated cylinder which holds 2 liters of water.




                        










4.0 Conclusion
            For the low or high achiever students, use uniform non-standard units to measure and compare volumes will emphasize filling each container with water to the top. Compare the volumes of two liquids by direct comparison. When comparing volumes of liquids, containers must be filled to the top. Then students can catch up the capacity. They will be more understanding about the capacity or volume before them using the graduated container.
            They investigate the volumes of two different containers of different sizes by filling the containers with water using a graduated cylinder. Students also engage in measuring volumes of liquids using measuring graduated cylinder. They will easily to catch up what are being told by teacher. Learning how to use a graduated cylinder is a crucial step. This guide will therefore endeavor the correct procedure to find the volume of a liquid using a graduated cylinder.
            In conclusion, students’ skills on predicting should be increase and should know basic measuring equipment. Then, students should be able to contrast and compare objects geometrically and able to measure volume of liquid.



5.0 Bibliography