Class 11 Physics practical reading To measure internal diameter and depth of a given beaker/calorimeter and hence find its volume.

Aim

To measure internal diameter and depth of a given beaker/calorimeter and hence find its volume.

Apparatus Required

A vernier calliper, a calorimeter and a magnifier.

Theory

Total reading in a vernier calliper = [N + (n x V.C.)] cm  

Volume of calorimeter 

                    V = (πd²h)/4 = .......... cm³

Here d is the diameter and h is the depth of the calorimeter.

Procedure

1. Read the main scale and find the value of one main scale division (M.S.D). Also calculate the vernier constant using V.C. = 1 M.S.D. - 1 V.S.D. (ii) Find the zero error, if any, positive or negative and record it.

Measurement of internal diameter 

2. Put the pair of upper jaws of vernier callipers into the calorimeter and adjust the position of jaws till the jaws gently touch the wall of the calorimeter. 

3. Note the main scale (N) and vernier scale (n) readings. 

4. Turn the internal side of beaker or calorimeter through 90° and again note the values of N and n. This completes one set of observation.

5. Repeat above steps two or more times at two different places of the calorimeter. 

6. Apply zero corrections to get correct readings. 

Measurement of Depth of Calorimeter 

7. Keep the right edge of main scale strip (M) on the upper edge of the calorimeter and move the vernier scale in such and way that the strip (E) attached to it touch the bottom of the colorimeter. Clamp the vernier scale with the help of screw S. 

8. Note the main scale reading and the number of coinciding vernier scale divisions and record them 

9. Repeat the process two more times at different positions.

Observations

Precautions

1. The movement of vernier scale on the main scale should be smooth. If not, oil it and clean the vernier callipers. 

2. The body should be gripped firmly between the jaws. 

3. Vernier constant and zero error should be carrefully calculated and recorded. 

4. Observations should be taken at right angles at one place. 

5. Use the magnifying lens to find the number of coinciding vernier divisions.

Sources of Error

1. Some errors may be creep due to parallex. 

2. The jaws may not be at exactly right angles to the main scale.