-
7/30/2019 Science Form 3 Unit 5
1/6
----------------------------------------------
UNIT 5: ELECTRICITY
5.1Sources of Electricity- Electrical energy which is u
power.
- Other sources of electrical(a) Dry cell
Sci
--------------------------------------------------------------------
ed every day is supplied by electric power stations
nergy are:
ence Notes Year 5
------------------------
1
or hydroelectric
-
7/30/2019 Science Form 3 Unit 5
2/6
----------------------------------------------
(b) Accumulator
(c) Dynamo
Sci
--------------------------------------------------------------------
ence Notes Year 5
------------------------
2
-
7/30/2019 Science Form 3 Unit 5
3/6
----------------------------------------------
(d) Panel of solar cells
5.2Electrical Circuits- An electric circuit is the pat- A simple
electric consists o
(a) Dry cell(b) Bulb(c) Connecting wires
Sci
--------------------------------------------------------------------
h of an electric current.
:
ence Notes Year 5
------------------------
3
-
7/30/2019 Science Form 3 Unit 5
4/6
----------------------------------------------
- Some of the electric circuit
- The diagram below shows t
(A) Series Circuit- When circuit components li
called a series circuit
- The electric current flows oof an electric source
- In a series circuit, if one parbecomes incomplete and t
Sci
--------------------------------------------------------------------
components and their symbols are shown in the be
he flow of electric current in a complete circuit.
ke a bulb is connected from end to end or in a row,
n only one path from the positive terminal to the n
t of the circuit is disconnected or the bulb is burnt,
e other bulbs will also be put out.
Series circuit
ence Notes Year 5
------------------------
4
low:
the circuit is
gative terminal
the circuit
-
7/30/2019 Science Form 3 Unit 5
5/6
----------------------------------------------
(B) Parallel Circuit- In a parallel, electric compo- There is
more than one pa- In a parallel circuit, if one b
another path. Other bulbs
5.3The Importance of safety Prec- Accidents will occur if the
u
source with wet hands and
- Some of the safety precaut(a) Dont touch electric wir(b) Dont
replace broken f(c) Dont use electrical app(d) Dont put any object
in(e) Dont repair any electri(f) Turn off the main switc(g) Dont
connect too man(h) Dont use any electric p(i) Dont play near a
powe(j) Dont use an electric wi
- Some steps to be taken wh(a) Turn off the main switc(b) Dont
touch the victim.
insulator
(c) Give first aid to the vict(d) Send the victim to a cli
Sci
--------------------------------------------------------------------
nents are arranged side by side and parallel to one
h for the flow of electric current
ulb is spoilt or removed, electric current will still flo
re still flow through another path. Other bulbs are
Parallel circuit
utions in the Use of Electricity
se of electricity is not carefully managed such as to
using an electrical wire which insulator has come o
ions when using electricity are:
es with wet hands
se wire with ordinary wire
liances during thunder or lighting
o a socket pole
cal appliance or electrical circuit yourself
h before an electric is repaired
electric plugs to the same power source
lug that is broken or cracked
r source
re which insulator has come off.
en electric shock occurs are:
h immediately
Separate the victim from electric source by touch
im
ic or hospital immediately
ence Notes Year 5
------------------------
5
another
through
still light.
ching an electric
f.
ith a dry
-
7/30/2019 Science Form 3 Unit 5
6/6
----------------------------------------------
Sci
--------------------------------------------------------------------
ence Notes Year 5
------------------------
6
