simple projects

How to Make a night lamp 

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How to make night lamp

To make a night lamp we need 

And see this video 

Inverter (DC & AC)

Is free energy is possible? 

ü  video about free energy 

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What is Transformer 

ü  Transformer is a Device that transfer electric power

ü  Transformer operates on ac supply

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How to Make a 50W LED portable 12v DC

Some time you need to make a strong light work with 12v DC, but many floodlight need more than 12V, this tutorial help you to make this 

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How to make Dc to Dc converter

When you make a project and such as Audio amplifier or portable Floodlight you need large DC voltage such as 24V, 30V, 35V, 50V, 60V …or more,

This tutorial helps you to convert 12V DC to any voltage you need

Some time you need to make a strong light work with 12v DC, but many floodlight need more than 12V, this tutorial help you to make this 

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Power calculation

Watt definition

 

Watt is the unit of power (symbol: W).

The watt unit is named after James Watt, the inventor of the steam engine.

One watt is defined as the energy consumption rate of one joule per second.

1W = 1J / 1s

One watt is also defined as the current flow of one ampere with voltage of one volt.

1W = 1V × 1A

Kilowatt-hour definition

Kilowatt-hour is an energy unit (symbol kWh or kW•h).

One kilowatt-hour is defined as the energy consumed by power consumption of 1kW during 1 hour:

1 kWh = 1kW • 1h

One kilowatt-hour is equal to 3.6•10⁶ joules:

1 kWh = 3.6•10⁶ J

The energy E in kilowatt-hour (kWh) is equal to the power P in kilowatts (kW), times the time t in hours (h).

E_(kWh) = P_(kW) • t_(h)

Table of unit prefixes of watt

name	symbol	conversion	example
picowatt	pW	1pW = 10-12 W	P = 10 pW
nanowatt	nW	1nW = 10-9 W	P = 10 nW
microwatt	μW	1μW = 10-6 W	P = 10 μW
milliwatt	mW	1mW = 10-3 W	P = 10 mW
watt	W	-	P = 10 W
kilowatt	kW	1kW = 103 W	P = 2 kW
megawatt	MW	1MW = 106 W	P = 5 MW
gigawatt	GW	1GW = 109 W	P = 5 GW

convert watts to kilowatts

The power P in kilowatts (kW) is equal to the power P in watts (W) divided by 1000:

P _(kW) = P _(W) / 1000

convert watts to milliwatts

The power P in milliwatts (mW) is equal to the power P in watts (W) times 1000:

P_(mW) = P_(W) • 1000

convert watts to dBm

The power P in decibel-milliwatts (dBm) is equal to 10 times base 10 logarithm of the power P in milliwatts (mW) divided by 1 milliwatt:

P_(dBm) = 10 • log₁₀( P_(mW) / 1mW)

convert watts to amps

The current I in amperes (A) is equal to the power P in watts (W) divided by the voltage V in volts (V):

I_(A) = P_(W) / V_(V)

convert watts to volts

The voltage V in volts (V) is equal to the power P in watts (W) divided by the current I in amperes (A):

V_(V) = P_(W) / I_(A)

convert watts to ohms

R_(Ω) = P_(W) / I_(A)²

R_(Ω) = V_(V)²/ P_(W)

convert watts to btu/hr

P_(BTU/hr) = 3.412142 • P_(W)

convert watts to joules

E_(J) = P_(W) • t_(s)

convert watts to horsepower

P_(HP) = P_(W) / 746

convert watts to kVA

The real power P in watts (W) is equal to 1000 times the apparent power S in kilo-volt-amperes (kVA) times the power factor (PF) or cosine of the phase angle φ:

P_(W) = 1000 • S_(kVA) • PF = 1000 • S_(kVA) • cos φ

convert watts to VA

The real power P in watts (W) is equal to the apparent power S in volt-amperes (VA) times the power factor (PF) or cosine of the phase angle φ:

P_(W) = S_(VA) • PF = S_(VA) • cos φ

Electrical Calculation

Volt (V)

Volt is the electrical unit of voltage.

One volt is the energy of 1 joule that is consumed when electric charge of 1 coulomb flows in the circuit.

1V = 1J / 1C

Ampere (A)

Ampere is the electrical unit of electrical current. It measures the amount of electrical charge that flows in an electrical circuit per 1 second.

1A = 1C / 1s

Ohm (Ω)

Ohm is the electrical unit of resistance.

1Ω = 1V / 1A

Watt (W)

Watt is the electrical unit of electric power. It measures the rate of consumed energy.

1W = 1J / 1s

1W = 1V • 1A

Decibel-milliwatt (dBm)

Decibel-milliwatt or dBm is a unit of electric power, measured with logarithmic scale referenced to 1mW.

10dBm = 10 • log₁₀(10mW / 1mW)

Decibel-Watt (dBW)

Decibel-watt or dBW is a unit of electric power, measured with logarithmic scale referenced to 1W.

10dBW = 10 • log₁₀(10W / 1W)

Farad (F)

Farad is the unit of capacitance. It represents the amount of electric charge in coulombs that is stored per 1 volt.

1F = 1C / 1V

Henry (H)

Henry is the unit of inductance.

1H = 1Wb / 1A

Siemens (S)

siemens is the unit of conductance, which is the opposite of resistance.

1S = 1 / 1Ω

Coulomb (C)

Coulomb is the unit of electric charge.

1C = 6.238792×10¹⁸ electron charges

Ampere-hour (Ah)

Ampere-hour is a unit of electric charge.

One ampere-hour is the electric charge that flow in electrical circuit, when a current of 1 ampere is applied for 1 hour.

1Ah = 1A • 1hour

One ampere-hour is equal to 3600 coulombs.

1Ah = 3600C

Tesla (T)

Tesla is the unit of magnetic field.

1T = 1Wb / 1m²

Weber (Wb)

Weber is the unit of magnetic flux.

1Wb = 1V • 1s

Joule (J)

Joule is the unit of energy.

1J = 1 kg • 1(m / s)²

Kilowatt-hour (kWh)

Kilowatt-hour is a unit of energy.

1kWh = 1kW • 1h = 1000W • 1h

Kilovolt-amps (kVA)

Kilovolt-amps is a unit of power.

1kVA = 1kV • 1A = 1000 • 1V • 1A

Hertz (Hz)

Hertz is the unit of frequency. It measures the number of cycles per second.

1 Hz = 1 cycles / s

Electrical &electronic Unit

Electrical & electronic units table

Unit Name	Unit Symbol	Quantity
Ampere (amp)	A	Electric current (I)
Volt	V	Voltage (V, E) Electromotive force (E) Potential difference (Δφ)
Ohm	Ω	Resistance (R)
Watt	W	Electric power (P)
Decibel-milliwatt	dBm	Electric power (P)
Decibel-Watt	dBW	Electric power (P)
Volt-Ampere-Reactive	var	Reactive power (Q)
Volt-Ampere	VA	Apparent power (S)
Farad	F	Capacitance (C)
Henry	H	Inductance (L)
siemens / mho	S	Conductance (G) Admittance (Y)
Coulomb	C	Electric charge (Q)
Ampere-hour	Ah	Electric charge (Q)
Joule	J	Energy (E)
Kilowatt-hour	kWh	Energy (E)
Electron-volt	eV	Energy (E)
Ohm-meter	Ω∙m	Resistivity (ρ)
siemens per meter	S/m	Conductivity (σ)
Volts per meter	V/m	Electric field (E)
Newtons per coulomb	N/C	Electric field (E)
Volt-meter	V·m	Electric flux (Φe)
Tesla	T	Magnetic field (B)
Gauss	G	Magnetic field (B)
Weber	Wb	Magnetic flux (Φm)
Hertz	Hz	Frequency (f)
Seconds	s	Time (t)
Meter / metre	m	Length (l)
Square-meter	m2	Area (A)
Decibel	dB
Parts per million	ppm

Units prefix table

Prefix	Prefix Symbol	Prefix factor	Example
pico	p	10-12	1pF = 10-12F
nano	n	10-9	1nF = 10-9F
micro	μ	10-6	1μA = 10-6A
milli	m	10-3	1mA = 10-3A
kilo	k	10 3	1kΩ = 1000Ω
mega	M	10 6	1MHz = 106Hz
giga	G	10 9	1GHz = 109Hz