Vernier calliper for std 8 to 12 GSEB Students, & ITI fitter measuring instruments.

Vernier calliper measuring instrument for ITI fitter and Gseb students.

Vernier calliper 

A calliper is a device used to measure the distance between two opposing sides of an object. It can be as simple as a compass with inward or outward-facing points. First the tips of the calliper are adjusted to fit across the points to be measured and the calliper is then removed and the distance between the tips is measured using a ruler.

The modern Vernier calliper was invented by Joseph R. Brown in 1851. It was the first practical tool for exact measurements that could be sold at an affordable price to ordinary machinists.   The Vernier Calliper consists of a main scale fitted with a jaw at one end. Another jaw, containing the vernier scale, moves over the main scale. When the two jaws are in contact, the zero of the main scale and the zero of the Vernier scale should coincide. If both the zeros do not coincide, there will be a positive or negative zero error.

1.Main Scale
The main scale consists of a steel metallic strip graduated in centimeters at one edge and in inches at the other edge . It carries the inner and outer measuring jaws. When the two jaws are in contact, the zero of the main scale and the zero of the Vernier scale should coincide. If both the zeros do not coincide, there will be a positive or negative zero error.

Vernier calliper

Least count of Vernier

Vernier calliper Main Scale

Vernier calliper 

Vernier calliper calculation

Vernier Calliper

vernier calliper least count

vernier calliper least count

vernier calliper least count

vernier calliper least count and Table

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

vernier calliper Measuring rectangle

2. Vernier Scale
A vernier scale  slides on the strip. It can be fixed in any position by the retainer. On the Vernier scale, 0.9 cm is divided into ten equal parts.

3. Outer Measuring Jaws
The outer measuring jaws helps to take the outer dimension of an object

4. Inner Measuring Jaws
The inner measuring jaws helps to take the inner dimension of an object.

5. Retainer
The retainer helps to retain the object within the jaws of the Vernier calipers.

6.  Depth Measuring Prong
The depth measuring prong helps to measure the depth of an object.

Least Count

The least count or the smallest reading which you can get with the instrument can be calculated as;

First calculate the least count and only then place the object between the two jaws.

Record the position of zero of the Vernier scale on the main scale.
Calculating the Reading

When a body is between the jaws of the Vernier Calliper.

More details view video:

Vernier calliper video Measuring rectangle practical.

pH value of solution and fruit juices GSEB std 8 to 12 Science

ph Value of Fruit juice

To determine the pH value of solution and fruit juices with the use of pH-paper approximately.

AIM  : To determine the pH value of solution and fruit juices with the use of pH-paper approximately

APPARATUS   : Seven glass  test tubes, one dropper, Test tube stand, and glass rod. Dilute hydrochloric acid solution,Lemon juice, Tomato juice, Distilled water, Sodium chloride solution, Sodium hydroxide solution, Sodium carbonate solution,

THEORY  :  [ The pH scale runs from 0 to 14 ]

If the pH of a solution is 7 it is a neutral solution. pH of acid is less then seven and that of base is more than seven.

Thus the nature of solution whether neutral, acidic or basic can be known by knowing by pH value of  solution. In the school laboratory pH value is determined by using pH papers. The basic principle of the pH paper is that it undergoes a suitable change in colour which is characteristic of the pH of the test sample of the solution. In this way pH paper is an indicator in different media of solutions giving different colour.

In the laboratory red and blue litmus papers are also used to find pH value less than 7 pH, more than7pH and 7pH.

pH value of solution and fruit juices

ph value of Dilute hydrochloric acid

pH value of solution and fruit juices

ph vales of Sodium chloride solution

ph vales of different Fruit juice

ph values table 

CONCLUSION

PRACTICAL USES : From pH value the property of substance or solution whether acidic, neutral or basic can be determined.

Angle of deviation of GLASS PRISM, GBSE practical for std 11 & 12.

Angle of Deviation of Glass Prism

ANGLE OF DEVIATION OF GLASS PRISM, 

12.1  AIM :-

Determine with the help of pins, the angle of the given glass prism. Determine the values of angle of emergence and angle of deviation for four different values of angle of incidence. Hence prove that  i + e = A +d.

PRINCIPLE : Reflection and refraction of light.

APPARATUS:  Glass Prism, Drawing paper, Drawing board, Pencil, Ruler, Pin, Protector,

PRECAUTIONS

Ø    While marking the position of a prism with pencil, the prism should not be disturbed.

Ø   A prism should be carefully put back exactly at the marked position.

Ø    While pressing the heads of the pins for fixing them use metal coin or a hard object so that you do not hurt your palm.

Ø    Do not press the pins very hard in the board otherwise it becomes difficult to remove them afterwards.

Ø   See that the pins pushed in the board remain perpendicular to the board.

PROCEDURE :

Take paper and pin it on Drawing board. 

Now take Glass prism and put it on center of Drawing board paper.

Mark the edges of the prism with pencil.

Angle of Deviation of Glass Prism Practical

Draw line P₁ M perpendicular  to prism base BC.

Insert two pins vertically P₁ & P_2..

Place the Prism on its original position.

NOTE :- Pins should be 3 – 4 cm. away from each other.

Observe pins from the side AB and insert two pins P’₁ & P’₂ such that images of P₁ ,P₂ and pins P’₁ & P’₂ are collinear.

Angle of Deviation of Glass Prism Procedure

Draw line Q₁ N perpendicular  to prism base BC

Insert two pins verticallyQ₁ & Q_2.

Angle of Deviation of Glass Prism Procedure

Place the prism on its original position

Observe pins from the side AC and insert two pins Q’₁ & Q’₂ such that images of Q₁ ,Q₂ and pins Q’₁ & Q’₂ are collinear.

Angle of Deviation of Glass Prism Procedure

Measure angle with protector ÐP’₁OQ’_1.

Angle of PRISM = ÐP’₁OQ’₁  / 2.

Angle of Deviation of Glass Prism Procedure

For more details view Video

Angle of Prism:

Influence of Heat (temperature) and Chemicals on the Pigments from Root and Tissues of Plant. std 11 & 12 biology

Study the Influence of Heat (temperature) and Chemicals on the Release of Pigments from Root and other Tissues of Plant

Influence of heat on Beat root

AIM :-

To study the influence of heat (temperature) and chemicals on the release of pigments from root and other tissues of plant.

INSTRUMENTS AND MATERIALS

Test tubes, cork borer, blade,  beakers, measuring cylinder, thermometer, burner,

Fresh beet roots, alcohol, formalin, benzene, distilled water, ice cubes. 

Observation :-

Table  1 : Effect of temperature on leaching of pigments from the beet root.

Conclusion

Betacyabin is present in the cell sap of beet root in vacuoles when beet root is kept at  high temperature the permeability of cell membrane is effected. High temperature damages the membrane and pigment leaks out from the membrane. This leaking is maximum at high temperature.

Observation :-

Table  2 : Effect of various chemicals on the permeability  on the cell      membrane.

Conclusion:

The  organic solvents like formalin and alcohol damage the cell membrane by dissolving fat and denaturing proteins. This permeability of cell membrane increases. So more leaking of pigment takes place. 

More details view video:

Study the Influence of Heat (temperature) and Chemicals on the Release of Pigments from Root and other Tissues of Plant

To test the presence of Carbon monoxide and Sulphur dioxide in the atmosphere. Biology std 11 & 12

To test the presence of Carbon monoxide and Sulphur dioxide in the atmosphere.

Test of Carbon  and Sulphur dioxide

INSTRUMENTS
Filter paper,  
Palladium or Platinum chloride, Acidic potasium dichromate.
Test for Carbon monoxide
Filter paper deep in chemical
Keep where transportation is more and smoke of automobiles is very high
View the changes on filter paper.
Slowly slowly it gets change in colour.
After some times 
Finally you see the change in colour that is due to Carbon monoxide is presence in Air.

Test for Sulphur dioxide
Filter paper deep in chemical
Keep where transportation is more and smoke of automobiles is very high
View the changes on filter paper.
Slowly slowly it gets change in colour.
After some times 

Finally you see the change in colour that is due to Sulphur dioxide  is presence in Air.

For more details view Video

To test the presence of Carbon monoxide and Sulphur dioxide in the atmosphere.