SPM Revision Notes
PHYSICS: Topics 1 to 5
Mechanics, Heat and Light
Units
Base Quantity
SI Unit
Symbol
Mass, m
kilogram
Kg
Length, l
meter
m
Time, t
second
s
Temperature, T
kelvin
K
Current, I
ampere
A
Prefix
Value
Symbol
Example
giga
× 109
G
gigawat
Symbol for
example
GW
mega
× 106
M
megawat
MW
kilo
× 103
k
kilometer
km
deci
× 10-1
d
decimeter
dm
cent
× 10-2
c
centmeter
cm
milli
× 10-3
m
millimeter
mm
micro
× 10-6
μ
micrometer
μm
Scalar and Vector Quanttes
• Scalar quanttes are physical quanttes with only
magnitude.
• Vector quanttes are physical quanttes having both
magnitude and directon.
Scalar Quantities
Vector Quantities
Distance
Displacement
Speed
Velocity
Mass
Weight
Energy
Momentum
Temperature
Pressure
Time
Acceleraton
Power
Force
Density
Impulse
Force and Moton
change of distance
speed
time taken
total distance travelled
average speed
total time taken
change in velocity v u
acceleration, a
time taken
t
Equatons of Linear Moton with Uniform
Acceleraton
u v
s
t
2
v u at
1 2
s ut at
2
v 2 u 2 2as
s : displacement
u : initial velocity v : final velocity
t : time taken
a : acceleration
Newton’s Laws
• 1st Law of moton: (Law of inerta)
– Every object will contnue in its state of moton with uniform
velocity or at rest unless it is acted upon by an external force.
• 2nd Law of moton:
– If an external resultant force acts on the object, it will produce
a change in moton (called acceleraton) which is proportonal
to the force and inversely proportonal to the mass of the
object, ie. F = ma
• 3rd Law of moton:
– For every acton (force), there is an equal and opposite
reacton (force).
Momentum
• Momentum is the product of mass and
velocity, p =...