BASIC ELECTRICITY OBJ
01-10: ACDCCBBDDB
11-20: DBBCCACCCD
21-30: DCDDBCCBBC
31-40: BBACDBABAA
41-50: BABBAABDCA
===================================
(1a)
R¹/2 = 6.5Ω – 2Ω
R¹/2=4.5Ω
R¹=2*4.5Ω
R¹=9Ω
Since R¹ is equal to R²,R² is also equals to 9Ω
===================================
(2a)
RMS voltage:
Vrms = 120 / √2 = 120 / 1.414 = 84.84 V
(2b)
Frequency:
ω (angular frequency) = 314.2 rad/s
f (frequency) = ω / 2π = 314.2 / (2 × 3.14) = 50 Hz
(2c)
Average value:
The average value of a sine wave is 0, since it oscillates equally around 0.
(2d)
Instantaneous voltage at t = 2 ms:
Convert time to radians:
t = 2 ms = 2 × 10^(-3) s
ωt = 314.2 rad/s × 2 × 10^(-3) s = 0.6284 rad
the instantaneous voltage:
V = 120 sin(0.6284) = 120 × 0.5888 = 70.656 V
===================================
(3a)
-Measuring Resistance
-Continuity Testing
(3bi) the expected ammeter reading will be the same as the current through the load.
(3bii)
Total resistance = Resistance of load + Resistance of ammeter
Total resistance = 750 Ω + 750 Ω
Total resistance = 1500 Ω
Using Ohm’s Law,
Current (I) = Voltage (V) / Resistance (R)
Current (I) = 15 V / 1500 Ω
Current (I) = 0.01 A or 10 mA
the actual current in the circuit is 0.01 A or 10 mA.
(3biii)
Power (P) = Current (I) x Current (I) x Resistance (R)
=Power (P) = 0.01 A x 0.01 A x 750 Ω
Power (P) = 0.075 W or 75 mW
===================================
(5a)
[PICK ANY FOUR(4)]
(i)Transformers
(ii)Circuit breakers
(iii)Switches
(iv)Surge Arresters
(v)Instrument Transformers
(vi)Busbars
(vii)Voltage regulators
(5b)
[PICK ANY TWO(2)]
(i)Mechanical Transmission Systems
(ii)Hydraulic Transmission Systems
(iii)Electrical Transmission Systems
(iv)Pneumatic Transmission Systems
(v)Hydrostatic Transmission Systems
(5c)
Neural line (neutral) completes the electrical circuit and carries return current WHILE Earth line (grounding) ensures safety by providing a path to earth ground and preventing electrical shocks.
===================================
(6ai)
(i) Faulty thermostat: The thermostat may be stuck or faulty, preventing the iron from heating up.
(ii) Broken heating element: The heating element may be broken or disconnected, preventing the iron from heating up.
(6aii)
(i) Check the power supply: Ensure the supply voltage is correct and stable.
(ii) Check the regulator: Verify that the regulator is functioning correctly and not stuck.
(iii) Check the thermostat: Test the thermostat for continuity and proper function.
(iv) Check the heating element: Inspect the heating element for breaks or disconnections.
(v) Check connections: Verify all connections are secure and not loose.
(6b)
(i) Multimeter
(ii) Wire stripper/cutter
===================================
(7ai)
(i) Load calculation: Determine the total electrical load required for the installation.
(ii) Voltage and frequency: Ensure the wiring system is suitable for the local voltage and frequency.
(iii) Environmental conditions: Consider temperature, humidity, and exposure to water or sunlight.
(iv) Cost and maintenance: Choose a system that balances cost with ease of maintenance and repair.
(7aii)
(i) Turn off power supply: Ensure the mains power is switched off before starting work.
(ii) Use personal protective equipment (PPE): Wear gloves, safety glasses, and a hard hat.
(iii) Insulate tools: Use insulated tools to prevent electrical shock.
(iv) Follow wiring regulations: Adhere to local electrical codes and regulations.
(7b)
(i) Switches
(ii) Sockets
(iii) Plug Boxes
(iv) Ceiling Roses
===================================
COMPLETED….We Remain Your Favourite Site.
Ensure You Subscribe For Your Next
Paper
===================================
Leave a Reply