1. Vernier Caliper

Vernier Caliper is a length measuring instrument which can be used to measure the length

of an object with accuracy up to 0.1 mm. term use is sliding profits can be used to measure the

diameter of a marble, the diameter of a tube or ring, or into a tube.

In general, vernier caliper consists of 2 parts of the jaw fixed and sliding jaws. Vernier

Caliper also consists of 2 parts they are the main scale contained in the fixed jaw and scale

Nonius (Vernier) contained in the sliding jaw.

Figure of Vernier Caliper

Parts of a vernier caliper:

1. Outside jaws : used to measure external diameter or width of an object

2. Inside jaws : used to measure internal diameter of an object

3. Depth probe : used to measure depths of an object or a hole

4. Main scale : scale marked every mm

5. Main scale : scale marked in inches and fractions

6. Vernier gives interpolated measurements to 1/10 mm or better

7. Vernier gives interpolated measurements in fractions of an inch

8. Retainer : used to block movable part to allow the easy transferring of a

measurement

Ten main scale has a length of 1 cm, in other words, a distance of 2 main scales adjacent

to each other is 0.1 cm. Whereas ten nonius scale has a length 0.9 cm, in other words, a distance

of 2 nonius scale adjacent to each other is 0.09 cm. So different from one main scale with a

nonius scale is 0.1 cm - 0.09 cm = 0.01 cm or 0.1 mm. So that the smallest scale of the vernier

caliper is 0.1 mm or 0.01 cm.

Accuracy of the vernier caliver is half the smallest scale. So vernier caliper accuracy is:

With the precision of 0.005 cm, then vernier caliper can be used to measure the diameter

of a marble or a ring with a more precise (accurate). As already explained earlier that s vernier

caliper could be used to measure the outside diameter of a marble, the diameter of a tube or ring

as well as to measure the depth of a tube.

This following will be explain how to use vernier caliper.

a. Measure the outside diameter . To measure the outside diameter of an object ( marbles)

can be done with the following steps.

• Slide the sliding jaw vernier caliper to right so that the measured object can be signed

between the two jaws (the jaw sliding and fixed jaws)

• Place the object to be measured between the two jaws.

• Slide the slider to left jaw so that the object is measured squeezed by both jaws

• Record the measurement results

b. Measure the inside diameter. To measure the inside diameter of an object (ring diameter)

can be done with the following steps.

• Slide a little the sliding jaw to right.

• Place objects / ring to be measured so that both jaw entered into the object / ring

• Slide the slider to right jaw so that both of jaw touches both walls of the object / ring

measured

• Record the measurement results

c. Measure the depth. To measure the depth of an object / tube can be done with the

following steps.

• Place the tube to be measured in the upright position.

• Rotate the term (upright position), then place the tip of the tube shove to the surface to

be measured therein.

• Slide the slider to down so that the jaw tip of vernier caliper touch the bottom of tubes.

• Record the results of measurements.

To read the measurement results using a vernier caliper can be done with the following steps:

Read the main scale or a scale which coincides exactly in front of the nearest zero point

Nonius scale.

• Read the appropriate Nonius scale coincides with the main scale.

• The measurement results given by the equation:

Result = Main Scale + (Nonius scale which coincides shove the smallest scale x) = Main Scale

+ (Nonius scale which coincides x 0.01 cm)

Because (three decimal places), then the results of measurement readings (xo)

also must be expressed in 3 decimal places. Unlike the ruler, on a scale vernier caliper Nonius,

you can never estimate the last digit (decimal to-3) so that you can just give the value 0 for

decimal to-3. So that the measurement results using can shove you report as:

Length, L = xo + x

Example, L = (4,990 + 0,005) cm

2. Mikrometer Screw

Micrometer screw is a measuring instrument of length where, its has a high level of

accuracy. Micrometer screw can be used to measure the thickness of the paper, the diameter of

thin wire, thin plate thickness which requires a high level of accuracy.

Figure of micrometer screw

Parts of mikrometer screw :

Yoke : The C-shaped body that holds the anvil and barrel in constant relation to

each other. It is thick because it needs to minimize flexion, expansion, and

contraction, which would distort the measurement. The frame is heavy and

consequently has a high thermal mass, to prevent substantial heating up by

the holding hand/fingers. It is often covered by insulating plastic plates

which further reduce heat transference.

Explanation: if you hold the frame long enough so that it heats up by

10°C, then the increase in length of any 10 cm linear piece of steel is of

magnitude 1/100 mm. For micrometers this is their typical accuracy range.

Micrometers typically have a temperature specified, at which the

measurement is correct.

Anvil :The shiny part that the spindle moves toward, and that the sample rests

against.

Spindle :The shiny cylindrical part that the thimble causes to move toward the

anvil.

Thimble/Rapid drive :The part that one's thumb turns. Graduated markings.

Scale barrel :The stationary round part with the linear scale on it. Sometimes vernier

markings.

Spindle lock : The knurled part (or lever) that one can tighten to hold the spindle

stationary, such as when momentarily holding a measurement.

Similar with vernier caliper, micrometer screw consist of:

• fixed jaw which contains the main scale is expressed in units of mm. The length of the main

scale micrometer generally reach 25 mm. distance between two adjacent main scale is 0.5

mm.

• threaded shaft mounted on the cylinder player (thimble). At the end of the thimble contained

the line that divides the scale into 50 equal parts called Nonius scale.

• sliding jaw associated with the thimble, which is used to hold the object to be measured

along with the jaw fixed.

If the thimble is moved one full rotation, so axis will then forward / backward 0.5 mm. Because

the outer sheath has a 50 scale, the smallest scale micrometer screw is 0.5 mm / 50 = 0.01 mm.

The accuracy of the micrometer screw is half the smallest scale. So precision micrometer

screwis:

With the precision of 0.005 mm, the micrometer screw can be used to measure the thickness of

paper or thin wire with a diameter of more precise (accurate).

To use the micrometer screw can be done by following these steps:

•Turn the thimble (big player) counter-clockwise so that the space between the fixed jaw with

sliding jaw enough to put the object to be measured.

• Place the object to be measured between the fixed jaw and the jaw slide.

• Then turn the thimble (major player) in a clockwise direction so that the measured object

caught by the jaw fixed and sliding jaws.

• Turn the small player (toothed wheels) in a clockwise direction so that the scale of Nonius in

large player does not move anymore.

• Read the measurement result.

To read the results of measurements using a micrometer screw can be done in steps as follows:

• Determine the main scale value that is closest to the cylinder casing (thimble) from sliding

jaw (or the main scale which is right in front of / coincides with the outer cylinder casing

shear jaws)

• Determine the value of a Nonius scale that coincides with a horizontal line on the main scale

of measurement results expressed by the equation:

• Result = Main Scale + (Nonius scale which coincides x smallest scale micrometer screw)

= Main Scale + (Nonius scale which coincides x 0.01 mm)

Because x = 0.005 mm (three decimal places), then the results of measurement readings

(xo) must also be expressed in 3 decimal places. Because we do not need to estimate the last digit

(decimal to-3) then we will just give the value 0 for decimal to-3. so that the results of

measurements using a micrometer screw can you report as:

Length, L = (Xo + X)

Example, L = (3,250 + 0,005) mm

3. Stopwatch

A stopwatch is a handheld timepiece designed to measure the amount of time elapsed

from a particular time when activated to when the piece is deactivated. There are 2 types of

stopwatches that is digital and analog stopwatch. Use a digital stopwatch more easily than

analog because the digital stopwatch measurement results can be read directly in the form of

numbers. In the following description will discuss the analog stopwatch.

Figure of analog stopwatch :

In general, analog stopwatch consists of:

• Button Start, Stop and reset are used to start, stop and repeat the measurement time.

• Scale in seconds, the scale was developed circular edge section with a distance between the

scale of 0.2 seconds.

• Needle length, which serves as a pointer measurement results in seconds. Scale in minutes,

is structured circular scale with the distances between the scale of 1 minute.

• short needles, which serves as a pointer of time in minutes.

When the long needle moves one full rotation, then the hour hand will move a scale. For 1 round

needle length = 60 seconds, 1 minute = 60 seconds

As mentioned earlier, from the smallest scale is 0.2 seconds (distance between the scale on the

scale of seconds). Accuracy of the stopwatch is half of the smallest scale. So the precision of a

stopwatch is: x = ½ x 0,2 second = 0,1 second.

With the precision of 0.1 seconds, the stopwatch can be used to measure time more carefully

(accurate) compared to the clock (watch).

To measure time using the stopwatch can be done by following these steps:

• Prepare the object to be measured is time, for example you want to measure the period of a

pendulum swing.

• Press the start button to start the measurement.

• If you want to stop the measurement click the stop button (this button together with the start

button).

• Then read the results of measurements that you earn, declare the results within seconds.

(Remember 1 minute = 60 seconds)

• If you want to repeat (position the needle stopwatch to the point 0) then press the reset

button (this button also becomes one with the start and stop)

To read the measurement results using a stopwatch can be done with the following steps:

• Read the scale indicated by the needle length (this is measured in seconds).

• Read the scale indicated by the short needle (this is measured in minutes).

• The measurement results given by the equation:

Result = reading scale by a long needle scale + readings by short needles

Because 1 minute = 60 seconds, then, the measurement results can be expressed as:

Result = {scale on the needle length + (60 x scale on short needle)} seconds.

Because x = 0.1 seconds (1 decimal), then the results of measurement readings (x o) must be

expressed in a decimal. As well as the length measuring instrument, the measurement results

using a stopwatch to your report as:

Time, t = xo + x

Example, t = (160,8 + 0,1) detik

4. Spring Balance

Spring balance is equipped with two types skla, the scale of the mass scale unit [Pounds] and skla unit

magnitude force [Newton]. This would mean, can spring balance used to measure the mass and weight of

the object.

Function

Spring balance (dynamometer) is a simple scale that uses a spring as a tool to determine which

measured the mass of the object measuring the tension spring balance spring, which in fact is the

pressure.

How to use a spring balance

Objects to be measured its mass, hung on hooks balance. scale in

show the balance pointer, the same view of the mass of the object to be measured.

scale unit mass scale in the balance sheet show the pointer is five, so mass of the object that mesuered

is five.

5. Three Arm Balance (Ohause Balance)

Balance is a measuring tool used to measure the mass of an object. In this lesson we will

discuss the balance of three arms as one measure the mass of the most commonly found on

balance sheets labolatorium.Three arm balance (often referred to as the Ohause Balance) has a

limit of measuring up to 600 grams.

Figure of Ohause Balance :

Balance consists of three arms:

• Buffer expenses used to place the object to be measured.

• Arm The balance sheet consists of 3 arms of the rear arm which has a scale of 0-100gram

with the distances between the scale of 10 grams. Arm located in the middle of a scale from

0-500gram with the distance between the scale is 100 grams. and arm at the front which has

a scale of 0-10 with the distances between the scale of 0.1 grams.• Weight (earrings) that

are placed on each sleeve that slides and a pointer-shear measurements.

• Point 0, which is used to determine the point of equilibrium.

The smallest scale of the balance sheet is 0.1 grams (ie the distance between the scale at which

the front arm) Accuracy of the balance sheet is half the smallest scale. So the accuracy of the

balance sheet are:

x = ½ x 0,1 gram = 0,05 gram

With the precision of 0.05 grams, then the balance of three arms can be used to measure the mass

of an object with a more precise (accurate). To measure the mass of an object using a balance of

three arms can be done by following these steps:

• Prepare the object whose mass would be measured, then place the object to the above buffer

load (the balance sheet to place the object to be measured).

• Scroll Earrings (weights) on each arm starting from most major ballast to ballast the

smallest such that the arms balance in equilibrium (horizontal) berimpitnya marked with

horizontal lines at the end of the arm with the point 0 (zero).

• After the equilibrium arm position, then read the measurement results that you get.

To read the measurement results using a balance of three arms can be done in steps as follows:

• Read the scale indicated by the earrings (weights) on each arm of the balance sheet.

• The measurement results given by the equation: Result = reading of the scale on the middle

arm of the scale readings on the arm + Rear + scale readings on the front arm

Because x = 0.05 grams (two decimal), then the results of measurement readings (xo) must be

expressed in two decimal places. Like the lat long measurement, the measurement results using

the balance sheet to your report as:

Mass, M = xo + x

Example, M = ( 322,75 + 0,05) gram