1f physics (meas-instr)

The World of PHYSICS…

VARIOUS AND COMMON EXAMPLES OF MEASURING TOOLS:

foot rule – simply known as ruler

pull-push rule – known as the

carpenter’s best friend


EXAMPLE OF MEASURING TOOL:A vernier caliper is a wrenchlike tool that can directly measure small lengths. Once the caliper is adjusted to the width of the measured object, a reading is taken from a scale on the tool.


Slide rule - was a standard tool for engineers and scientists.

Operating on the principle that all mathematical computations may be carried out on sets of sliding

scales, the device looks much like a heavily calibrated ruler with a

movable mid-section.


EXAMPLE OF MEASURING TOOL:

Beam Scale – is often found in doctor’s offices, the beam scale uses small adjustable

weights called poises to balance the load. The weight

is measured from markings on the beam.


EXAMPLE OF MEASURING TOOLS:Outdoor Thermometer – like a red-dyed alcohol thermometer measures an outside air temperature of about 6° C (about 43° F). In a thermometer, an expanding fluid such as alcohol or mercury is trapped within a closed glass rod.


EXAMPLE OF MEASURING TOOL:Mercury and digital thermometers are the most common

types of household devices for

measuring body temperature. In mercury thermometers, an

increase in warmth causes mercury to expand and rise in a glass tube. Digital thermometers measure temperature with electronic sensors.



Most grandfather clocks are weight-

driven, which means they are powered by the pull of a hanging weight. A mechanism

called the escapement regulates the

incremental release of the weight’s

energy via toothed gears, which set other wheels in

motion.



Ornate sandglasses like this one were once

used to mark the passage of minutes

and hours. Flipping the glass causes the fixed

amount of sand to pass though its narrow

central hole in a consistent length of

time, creating a relatively accurate

measure. Generally called hourglasses

because an hour was their standard setting



This portable folding German sundial has a string gnomon (pointer), adjustable for accuracy at any latitude. As shadows fall across the sundial, the smaller dials show Italian and Babylonian hours. The dial also indicates the length of the day and the position of the sun in the zodiac.


EXAMPLE OF MEASURING TOOL:This Japanese clock was regulated by weights on a moving balance bar is called a lantern clock because of its distinctive shape. it features the one-hand design common in most clocks until the 1650s.


EXAMPLE OF MEASURING TOOL:Portable clocks like the

Nüremberg egg became possible

with the development of

coiled springs as a power source for timekeeping

devices.



Liquid crystal forms from

various organic substances and takes its name

from the crystal-like properties of

liquids whose molecular

orientation changes when a

small electric current is applied.

It is used for digital clocks

known as LCD.



NIST F-1, an atomic cesium fountain clock, replaces the NIST-7, which served as the primary United States time standard from 1993 to the end of 1999. The new atomic timekeeper is so accurate that it could run for nearly 20 million years without gaining or losing a single second.

1f physics (meas-instr)

Technology

world of physics various

standard tool

world of physics slide

wrenchlike tool

mercury thermometers

beam scale

digital thermometers

small adjustable weights