PHYSICAL QUANTITIES & UNITS Hazrin Shah Bin Hj Azahari 08B0912 Mohammad Dedyardie Takong 08B0904 MICROMETER SCREW GAUGE 1. 2. 3. 4. Example : To find the thickness of a paper metre centimetre millimetre kilometre Use to measure very small value VERNIER CALIPERS Example : To measure the internal & external length Units commonly used Use to measure the internal and external diameter of object Use to measure longer length MEASURING TAPE Example : Length of a door LENGTH Instruments used Use to measure short length RULER Example : Width of a book 1. 2. 3. 4. Metre rule Measuring tape Vernier caliper Micrometre screw gauge OBJECTIVES • Use and describe how to use vernier scale and calipers • Use and describe how to use micrometer screwgauge VERNIER CALIPER Inside jaw Locking nut Main scale Vernier scale Outside jaw Roller Tail TYPES OF VERNIER CALIPER 1. Basic vernier caliper 2. Long Jaw vernier caliper TYPES OF VERNIER CALIPER 3. Knife Edge vernier caliper 4. Chiesel Shape vernier caliper VERNIER CALIPER 1. Vernier caliper is used to measure the: a) the external diameter of an object b) the internal diameter of an object c) depth of a tube 2. It is used to measure length to the nearest 0.01 cm or 0.1 mm SCALES IN A VERNIER CALIPER Main scale Vernier scale HOW TO USE A VERNIER CALIPER 1. Slide the vernier scale along the main scale so that an object can be inserted into the jaws (inside or outside jaw) HOW TO USE A VERNIER CALIPER 2. Read the main scale up to the zero line of the vernier scale HOW TO USE A VERNIER CALIPER 3. Read the vernier scale by looking for the line in the vernier scale which is exactly opposite any line in the main scale http://members.shaw.ca/r on.blond/Vern.APPLET/