To Determine The Thickness Of A Given Plate Using A Spherometer. | Grade Xi
0APPARATUS REQUIRED
- Spherometer
- Plate of known thickness
- Micrometer screw gauge
- Magnifying glass
THEORY
A spherometer is a device used to measure the radius of curvature of a spherical surface. It consists of a tripod or other support with a movable screw at the center. A spherical surface is placed on the tripod and the screw is turned until it just touches the surface. The distance between the screw and the tripod is then measured using the micrometer screw gauge. This distance is equal to the radius of curvature of the spherical surface.
The thickness of a plate can be determined using a spherometer by measuring the radius of curvature of the plate before and after it is placed on the spherometer. The difference between the two radii of curvature is equal to the thickness of the plate.
PROCESS
- Place the plate on the tripod and adjust the screw until it just touches the plate.
- Note the reading on the micrometer screw gauge.
- Remove the plate and place it on the spherometer.
- Adjust the screw until it just touches the plate.
- Note the reading on the micrometer screw gauge.
- The difference between the two readings is equal to the thickness of the plate.
- Take the three different readings of the thickness of the given plate and find their mean.
OBSERVATIONS
Reading on the micrometer screw gauge (before placing the plate): mm
Reading on the micrometer screw gauge (after placing the plate): mm
Difference between the two readings: mm
OBSERVATION TABLE
| Reading 1 | Reading 2 | Reading 3 |
|---|---|---|
| mm | mm | mm |
CALCULATIONS
Thickness of the plate: mm
RESULTS
The thickness of the given plate is mm.
PRECAUTIONS
- The plate should be clean and free of any dust or dirt.
- The screw should be turned slowly and carefully until it just touches the plate.
- The micrometer screw gauge should be read accurately.