LESSON
OBJECTIVES :
Familiarize with different system of unit of
measurements
Convert units of measurements
Solve measurements problems involving
conversion of units
LESSON 1 :
Solve Measurement
Problem Involving
Conversion of Units
WHAT
IS
PHYSICS ?
MEASUREMENTS
Where do we use
measurement ?
MEASUREMENT
Is the assignment of
numerical value to an
object’s physical properties
We need to assign units to
numerical quantity of
measurements to convey
the relative size of
magnitude of property
2 SYSTEMS OF UNITS
METRIC SYSTEM
Has 2 variations ; cgs and
mks system.
 The International System of Units
( SI system) from French Le
System International d’ Unites , is
the modern form of Metric System
 Metric or SI is more convenient
to use
2. English System
Makes use of fps system which is
the abbreviation of the fundamental
units which are feet, pounds,
seconds
 it does not use decimalization and
it’s not a multiple of 10.
DERIVED QUANTITIES
Are quantities resulting from the
combination of any of the
fundamental quantities.
Conversion of Units
CONVERSION UNIT – a ratio expressing
how many of one unit are equal to
another unit.
Steps in Unit Conversion:
Identify the value to be converted.
Find the conversion factors that can be used
to change the units.
Multiply the original value to the conversion
factor too eliminate and change the units.
Write the equivalence
SAMPLE PROBLEM : ( metric system)
1.1024 mm = ________ m
2.1,673 mg = _______ kg
3.35.8 km = _______ dam
4.0.46 g = ________ cg
5.2.6 kL= _________ L
EXERCISES :
1. 396 m to ___________km
2. 60 miles to feet
3. 47 cm to _____ inches
4. 8.65 yrs. to _____ sec
5. 12 m2 to _______ cm2
I. Metric to Metric Conversion
SAMPLE PROBLEM :
Nanotechnology is a term that embraces
the use of materials of size in the order of a
nanometer. What is 2.0 nanometer in (a)
meters and (b) centimeters?
SOLUTION:
 A. First form the conversion ratio or factor with the
meter at the numerator and the nanometer at the
denominator.
1 nm = 10 −9 m. Therefore our conversion ratio is
Multiply the original quantity by this conversion ratio
2.0 nm x =
2.0 x 10 ¯ 9 m
10 − 9
1 nm
 B. To convert to cm, multiply the
answer in letter a by the factor
2.0 x 10¯9 m x
1 cm
10¯2 m
= 2.0 x 10¯7 cm
II. Metric to English Conversion
SAMPLE PROBLEM :
How many pounds of chocolate are
there in 2.3 kg ?
 First form the conversion ratio or factor
with the pound at the numerator and the
kg at the denominator
1 lb. 0.4536 kg. ,
Ib.
0.4536 kg
 Multiply the original quantity by this
conversion ratio.
2.3kg x Ib.
= 5.07 Ib.
0.4536 kg
1. 1,357 mm = _____________m
2. 8 L = __________mL
3. 12O kg = __________ g
4. 6,000 s =________ min
5. 24.5 m =_________cm
6. 5 m =__________cm
7. ________ m= 6 km
8. A liter of chloroform has
a mass of 1490 grams.
Convert this mass to
kilograms.
A weightlifter can
lift 495 lbs. How
many kg is that ?
A certain car has mass
of 1920 kg . How many
tons is that ?
55 km to m
hr
s