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Quantities	Instruments	Cases of Usage	Limit of Precision	Range
Length	Meter Rule	To measure a book,pencil etc.	0.5mm	0.5mm-1m
Vernier Caliper	To Measure a cube, diameter of a tube	0.05mm	0.05mm-8cm
Micrometer screw Gauge	To measure thickness of pencil etc.	0.005mm	0.005mm-5cm
Volume	Measuring cylinder	To measure a small amount of water	0.5cm³	10cm³-100cm³
Beaker	To measure about a cup full of water	12.5cm³	25cm³-250cm³
Burrette	To measure volumes for titration	0.05cm³	10cm³-100cm³
Time	Clock	To measure large periods of time	1 sec.	1 sec.- several hours
Stopwatch	To measure specific periods of time>	1 millisecond	1 milisecond- several hours
Temperature	Mercury Thermometer	Temperatures between -5 to 105	0.5 degrees	-39º to 357ºC
Alcohol Thermometers	To measure mainly subzero temperatures	0.5 degrees	-115ºC to 78ºC
Thermocouple	any temperature above 0º	as acurate as the galvanometer is	0ºC to 1500ºC
Force	Spring Balances	to measure small forces	0.5N	0.5N-10N (varies somtimes)
Current	Ammeter	To measure currents	Dependent on the scale used	Dependent on the scale used

Section 2

This area will not be explained be explained in depth as most of it refers to practical activities which will or should be done during your Lab sessions.

Errors 2.3

Consider the following statement when calculating:
Calculation cannot increase the presicion or the number of significant figures
of measured quantities. If you really think about it it only makes sense because the answer for the problem cannot be more precise than the numbers you are working with. Therefore the precision of the number is said to be as presice as the least presice number in the problem. Therefore for the problem 2.2 x 4.57 the answer is 10.054 but its correct presicion is for it to be rounded of to two decimal places. So the the precise answer would be 10.1.

Errors 2.4

Possible sources of general errors in experiments include:

Viruses in digital instruments

Parallax- Incorrect eye position causes wrong reading to be taken. It can also be caused by not reading from the bottom of the meniscus.

Zero Error- Causes incorrect reading because the zero mark on the instrument used to measure is not aligned with the edge of the object or with a triple beam balance the zero marks are no in line.

Incorrect Calibration- You can say this is where the manufacturer causes the error. The error made is caused because the the instrument is not made properly.

Human Error- Caused because of human limitations eg. when taking a stopwatch reading some extra time may be in addition to the actual time because of the reaction time taken press the stop button.

Environmental Factors- This applies to taking readings such as temperature where the temperature of the environment might increase or decrease the correct reading on the thermometer

Errors 2.5

Parallax can be minimised by bringing the eye to the level of the apparatus. The diagram below will explain what i mean.

The following table covers both 2.6 and 2.7 which deals with the instruments used to measure differnt quantities and which instruments are best suited for measuring certain stuff based on their sensitivity accuracy and range.

Quantities Instruments Cases of Usage Limit of Precision Range

Length Meter Rule To measure a book,pencil etc. 0.5mm 0.5mm-1m

Vernier Caliper To Measure a cube, diameter of a tube 0.05mm 0.05mm-8cm

Micrometer screw Gauge To measure thickness of pencil etc. 0.005mm 0.005mm-5cm

Volume Measuring cylinder To measure a small amount of water 0.5cm³ 10cm³-100cm³

Beaker To measure about a cup full of water 12.5cm³ 25cm³-250cm³

Burrette To measure volumes for titration 0.05cm³ 10cm³-100cm³

Time Clock To measure large periods of time 1 sec. 1 sec.- several hours

Stopwatch To measure specific periods of time> 1 millisecond 1 milisecond- several hours

Temperature Mercury Thermometer Temperatures between -5 to 105 0.5 degrees -39º to 357ºC

Alcohol Thermometers To measure mainly subzero temperatures 0.5 degrees -115ºC to 78ºC

Thermocouple any temperature above 0º as acurate as the galvanometer is 0ºC to 1500ºC

Force Spring Balances to measure small forces 0.5N 0.5N-10N (varies somtimes)

Current Ammeter To measure currents Dependent on the scale used Dependent on the scale used

Other sections as said before will be cover during your lab sessions but I will leave the formulas for density and the gradient of a graph.

Density(p)=m (Mass)/v (Volume)

Gradient= y₂-y₁/x₂-x₁

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