prefixes

1. Instruments used for measuring time:pendulum clock/clock,watch and stopwatch

1.1. The pendulum clock uses a pendulum and the oscillation of a pendulum refers to a single cycle of a cyclic or repeating motion.The time for 1 complete oscillation is referred to the period of oscillation.

1.2. Micrometer screw gauge: measures to an accuracy of 0.01 mm

1.2.1. Micrometer screw gauge consists of anvil,spindle,sleeve,thimble and ratchet

2. 6)Amount of subtance(mole):mol

3. Physical quantities

3.1. -A quantity that can be measured and consists of a magnitude and unit.

3.2. -The quantities can be classified into two types:the Derived quantity and the Base quantity.

3.3. -Base quantity is the known as the fundemental quantity as it is independent of other physical quantities

3.4. -Derived quantity is defined by operations based on other physical quantities

4. Measurement of Length and time

4.1. The two types of errors are random errors and systematic errors.

4.2. Instruments used for measuring length:Measuring tape,metre ruler,vernier calipers and micrometer srew gauge

4.3. Metre ruler: measures to an accuracy of 0.01 cm

4.4. Measuring tape: measures to anaccuracy of 0.1 cm

4.5. Vernier calipers: measures to anaccuracy of 0.01 cm

4.5.1. Vernier calipers consists of inside jaws,outside jaws,vernier scale,main scale and depth bar