Download Electrical circuit symbols of components

M.E.S.INDIAN SCHOOL
Doha, Qatar
INDEX
S.
No.
FA-01
1
FA-01
2
FA-01
3
Activity
Reading electrical meters
(diagram based worksheet)
Ohm’s Law
(practical)
4
FA-01
Resistors in Series
(practical)
FA-01
Numerical Problems
FA-02
Effective resistance
1
(diagram based numerical
FA-02
Resistors in parallel
FA-02
Electromagnet
2
3
FA-02
4
FA-02
Sign
(matching type worksheet)
Units and Symbols
(multiple choice worksheet)
6
Submitted
on
Electrical Circuit Symbols
FA-01
5
Due
Date
(practical)
(make it yourself project)
Our Power Projects
(seminar)
Numerical Problem
5
Certified that ……………………………………………………..of class X-…..
has completed all the activities and experiments listed above.
Name and signature of the teacher:………………………………..
Electrical circuit symbols
Identify the component and fill in the table using the list given below.
(Open key, cell, variable resistor, wire joint, ammeter, closed key,
resistor, battery, voltmeter, crossing wire without joint, lamp )
…….Symbol……. ……………Component……………
Reading electrical meters
The voltmeter and ammeter readings in an Ohm’s law
experiment are shown on the left page. Record the voltmeter
and Ammeter readings and calculate the resistance.
Least count of voltmeter :…….……Range of voltmeter:……
Least count of ammeter:……………Range of ammeter:…………
S.No Voltmeter reading Ammeter Reading
Resistance
V (volt)
I (amp)
R = V/ I (Ω)
1.
2.
3.
4.
5.
Mean R
Plot a graph using the V – I values and calculate slope.
x1 =
x2 =
y1 =
y2 =
V(volt)
I (amp)
y2 - y1
Resistance = ---------- =
x2 - x1
Circuit Diagram
Least count of voltmeter :………..……
Range of voltmeter:……………..……
Least count of ammeter:………..………
Range of ammeter:………….………
Voltmeter reading
Ammeter Reading
S.No
V(volt)
I (amp)
1.
2.
3.
4.
5.
Mean
V – I Graph
I (amp)
Resistance
R = V/I (ohm)
V (volt)
Ohm’s Law
Date:
Aim: To verify Ohm’s law and to find the resistance of a
wire.
Apparatus: A battery, switch, rheostat, resistor, ammeter,
voltmeter, connecting wires.
Theory: At constant temperature, current flowing through a
conductor is directly proportional to the potential difference
across the ends of the conductor.
Procedure: Connect the circuit as shown in the diagram.
Record the least count and range of the ammeter and
voltmeter. Adjust the rheostat so that the current is very
low. Record the ammeter and voltmeter readings. Adjust the
rheostat to increase the current slightly. Record the new
ammeter and voltmeter readings. Repeat the experiment to
get five sets of voltmeter and corresponding ammeter
readings. Plot a graph of voltage against current.
Result:
1. Graph is a …………………………………line passing through
the origin. Current through the resistor is ……………………….
……………………………...........
to
the
potential
difference.
Ohm’s law is verified within the limits of experimental error.
2. Resistance of the given resistor = ……….…….Ω
Precautions.
1. Ends of the connection wires should be cleaned to
reduce contact resistance
2. Set the current to low value to avoid heating up of the
circuit.
3. Close the key only while taking the readings to avoid
heating.
Units and Symbols
Choose the correct answer
1. The SI unit of electric current is……….
a) volt
b) ampere
c) watt
d) joule
2. The symbol for a variable resistor is
a)
b)
c)
d)
3. Ω is the unit of ……
a)current b)Potential difference c) power d) Resistance
4. If one joule of work is done to move one coulomb between
two points, then the potential difference between those
points is……
a) one watt b) one ampere
c) one volt
d) one ohm
5.Which of the following is connected in parallel in a
circuit?
a)
b)
c)
d)
6. The unit of charge is ………….
a) coulomb
b)
ampere
c) volt
d) watt
7. If a bulb dissipates one joule of energy per second then
the power of the bulb is….
a) one volt b) one ampere
c) one ohm
d) one watt
8. Which is the symbol for the unit of current?
a) V
b) C
9.
c) A
d) W
is the symbol of a device used to …….current
a) measure
b) stop
c) control
d) supply
10. The unit ohm is related to which of the following?
a)
b)
c)
d)
Circuit Diagram
Least count of voltmeter :………………
Range of voltmeter:………………
Least count of ammeter:……………
Range of ammeter:……………
R1 = …………… R2 =……………
Rs = R1 + R2 = …………………
S.
No
Voltmeter reading
V (volt)
Ammeter Reading
I (amp)
1.
2.
3.
4.
5.
Mean R
Resistance
R = V/ I (Ω)
Resistors in series
Date:
Aim: To find the effective resistance when resistors are
connected in series.
Apparatus: A battery, switch, rheostat, two known resistors,
ammeter, voltmeter, connecting wires.
Theory: When connected in series effective resistance
increases. Combined resistance is equal to the sum of
individual resistances.
Procedure: Record the least count and range of the ammeter
and voltmeter. Record the values of the given resistors.
Connect the circuit as shown in the diagram. Adjust the
rheostat so that the current is very low. Record the
ammeter and voltmeter readings. Adjust the rheostat to
increase the current slightly. Record the new ammeter and
voltmeter readings. Repeat the experiment to get five sets of
voltmeter and corresponding ammeter readings. t. Calculate
the combined resistance of the given resistors.
Result:
1. Combined resistance of the given resistors = ………….Ω
2. Effective resistance is ………………….. than that of
individual resistors.
Precautions.
4. Ends of the connection wires should be cleaned to
reduce contact resistance
5. Set the current to low value to avoid heating up of the
circuit.
6. Close the key only while taking the readings to avoid
heating.
Numerical problems
1. A current of 0.5 A is drawn by a filament of an electric
bulb for 2 minutes. Find the amount of electric charge
that flows through the circuit.
2. How much work is done in moving a charge of 5 C
across two points having a potential difference 6 V?
3. An electric toaster draws a current of 5A when
connected to a 220V power supply. Find the resistance
of the heater.
4. Resistivity of Constantan at 20O C is 49 X 10-6 Ωm.
Find the resistance of the heating element of length
50cm and area of cross section 7.0 X 10-6 m2 at the
same temperature.
Effective Resistance
Find the effective resistance across PQ in the following
circuits.
P
Q
2Ω
3Ω
5Ω
4Ω
P
Q
6Ω
6Ω
6Ω
P
Q
6Ω
6Ω
4Ω
P
Q
7Ω
3Ω
6Ω
6Ω
P
Q
3Ω
P
Q
3Ω
P
Q
5Ω
Circuit Diagram
Least count of voltmeter :…………
Range of voltmeter :…………
Least count of ammeter:……………
Range of ammeter:…………………
R1 = …………… R2 =……………
Rp
R1 X R2
= ---------- = ………………
R1 + R2
S.
No
Voltmeter reading
V (volt)
Ammeter Reading
I (amp)
1.
2.
3.
4.
5.
Mean R
Resistance
R = V/ I (Ω)
Resistors in parallel
Date:
Aim: To find the effective resistance when resistors are
connected in parallel.
Apparatus: A battery, switch, rheostat, two known resistors,
ammeter, voltmeter, connecting wires.
Theory: When connected in parallel effective resistance
decreases. Reciprocal of combined resistance is equal to the
sum of the reciprocals of individual resistances.
Procedure: Record the least count and range of the ammeter
and voltmeter. Record the values of the given resistors.
Connect the circuit as shown in the diagram. Adjust the
rheostat so that the current is very low. Record the
ammeter and voltmeter readings. Adjust the rheostat to
increase the current slightly. Record the new ammeter and
voltmeter readings. Repeat the experiment to get five sets of
voltmeter and corresponding ammeter readings. Calculate
the combined resistance of the given resistors.
Result:
1. Combined resistance of the given resistors = ……..……. Ω
2. Effective resistance is ………………………………….. that of
individual resistors.
Precautions.
7. Ends of the connection wires should be cleaned to
reduce contact resistance
8. Set the current to low value to avoid heating up of the
circuit.
9. Close the key only while taking the readings to avoid
heating.
Electromagnet
Make an electromagnet and test its strength.
Materials required
- iron nail – one, 2” long
- insulated copper wire – one meter
-1.5V dry cell – one
How to construct- Wind the copper wire tightly on the iron
nail. Tie the end of the wire on the nail with a thread.
To test – remove the insulation from the ends of the wire.
Connect the ends to the terminals of the cell and hold the
nail near a pile of paper clips.
What did you observe:……………………………………………..
………………………………………………………………………….
……………………………………………………………………………
Suggest two ways to increase the strength of the
electromagnet.
1………………………………………………………………………..
2………………………………………………………………………..
Our Power Projects
The main power projects in India are Hydro-electric power
projects, Thermal power projects and nuclear power
projects.
Make a group of five students. Choose one of the power
projects in India and conduct a seminar on its advantages
and disadvantages.
( Your teacher may suggest the power project for you to avoid repetition)
Power project :…………………………………………………………
(eg: Bhakranangal Power project)
Location:………………………..……………….………………………
Type of project:…………….……………….………………………..
(Hydro/Thermal/Nuclear….)
My group will talk about the ……………………………………..
Of this project
( advantages/disadvantages)
My points:
…………………………………………………………………….
……………………………………………………………………..
…………………………………………………………………….
……………………………………………………………………….
……………………………………………………………………….
Numerical Problems
1. Three resistors of 2 Ω. 5 Ω and 3 Ω respectively are
connected in series. Find the effective resistance.
2. Three resistors of 2 Ω. 6 Ω and 3 Ω respectively are
connected in parallel. Find the effective resistance.
3. An electric bulb is connected to a 220 V generator.
What is the power of the bulb if the current through
the bulb is 0.50A?
4. A room heater can offer a maximum resistance of 100
Ω when 5 A current flows through it for one
minute. What is the maximum amount of heat
produced by the heater?
5. An electric kettle consumes 1 kW of electric power
when operated at 220 V. A fuse wire of what rating
must be used for it?
6.
Two lamps, one rated 100 W at 220 V, and the
other 60W at 220 V, are connected in parallel to
electric mains supply. What current is drawn from the
line if the supply voltage is 220V?
7. An electric room heater is rated 2kW. Calculate the
cost of using it for 2 hours daily for the month of
September, if each unit costs Rs. 4.00.