Kirchoff's Law

Kirchoff's Law

Before we start this lesson, let's play a game

Multiple Choice

Who did Kaneki from Tokyo Ghoul get his organ from.

• Rize

• Toka

• Hide

• Nishikio

Multiple Choice

What anime is this from?

• Naruto

• MHA

• DBZ

• Demon Slayer

Multiple Choice

from what anime this character comes ?

• Hunter x hunter

• my hero academia

• danganronpa

• Demon slayer

Multiple Select

Who is Gohan?

Multiple Choice

what is this anime

• Demon slayer

• hunter x hunter

• Dragon ball Z

• attack of titans

Multiple Choice

Who is this?

• Goku

• L

• Tanjiro

• Sasuke

• Kageyama

Multiple Choice

What are Naruto's powers?

• Naruto sucks and I don't watch it

• Nine tailed fox

• Rasengan

• Amaterasu

Multiple Choice

how is she and what's is its anime

• Himiko toga and from miss kobayashi dragon maid

• Himiko toga and villian, one piece

• Himiko toga and my hero academia

• Himiko toga and kakeguri

Multiple Choice

What anime is this from?

• Haikyuu

• Fairytail

• Tokyo Ghoul

• Erased

Multiple Choice

Who is this?

• Koro-Sensei

• Karma

• Karasuma

• Nagisa

Multiple Select

what anime is she from

• Dangaronpa

• one piece

• My hero academia

• HXH

Multiple Choice

Who is this?

• Kageyama

• Sasuke

• Kaneki

• Saitama

Multiple Select

how is norman ?

Multiple Choice

Who is this

• sasuke

• frieza

• naruto

Multiple Choice

Which is the correct quote?

• "I Naruto Uzumaki will be the greatest hokage, that's my nindo my ninja way."

• "I never go back on my word, that's my nindo my ninja way."

• "I help my friends in need, that's my ninja way."

• "I keep my promises and make them come true, that's my nindo my ninja way."

Multiple Select

how is she and were is she from

• Mother spider, from demon slayer

• rui, demon slayer

Multiple Choice

Who is this

• sakura

• vegeta

• naruto

Multiple Choice

Who is this.

• Yadomi

• L

• Sasuke

• Vegeta

Multiple Choice

Who is this

• bakugou

• deku

• frieza

Multiple Choice

How old is Naruto in this picture?

• 5-7

• 8-10

• 12-14

• 15-17

Multiple Choice

who is this

• sakura

• bakugou

• deku

Multiple Choice

Who turned Kaneki into a ghoul?

• Himself

• Touka

• Rize

• Dr.Mado

Multiple Choice

who is this

• vegeta

• deku

• todorki

Multiple Choice

Who is this?

• Chrollo

• Hisoka

• Killua

• L

Multiple Choice

who is this

• naruto

• sakura

• frieza

Multiple Choice

What anime is this from?

• Naruto

• Demon Slayer

• MHA

• God Eater

• HxH

Multiple Choice

Which one is natsu

• red hair boy

• blue hair

• black hair

• red hair girl

• yellow hair

Multiple Choice

How did Itachi die the first time?

• Sasuke

• Natural Causes

• Naruto

• Jiraiya

Multiple Choice

which one is naruto

• yellow hair

• black hair

• pink hair

Multiple Choice

What is Minato's last name?

• Uzumaki

• Uchiha

• Namikaze

• Senju

Multiple Choice

who is lucy???

• yellow hair

• black hair

• red hair boy

• red hair girl

• blue hair

Multiple Choice

What is Luffy's full name?

• Sir Luffy

• Elastic Luffy

• Luffy

• Monkey.D.Luffy

Multiple Choice

who is stronger natsu or grey

• natsu

• grey

Multiple Choice

Who is this?

• 01

• Touka

• 02

• Sakura

Multiple Choice

What is the first word in the Attack On Titan opening?

• You

• We

• Are

• There

Kirchoff's

Law

Kirchoff's Law_Intro

Kirchhoff’s circuit laws lie at the heart of circuit analysis. With the help of these laws and the equation for individual components (resistor, capacitor and inductor), we have the basic tool to start analyzing circuits. In this article, we will discuss Kirchhoff’s current and voltage law and how to employ them in circuit analysis.

History about Gustav Robert Kirchhoff

Gustav Robert Kirchhoff, a German physicist, was born on March 12, 1824, in Konigsberg, Prussia. His first research topic was the conduction of electricity. This research led to Kirchhoff formulating the Laws of Closed Electric Circuits in 1845. These laws were eventually named after Kirchhoff and are now known as Kirchhoff’s Voltage and Current Laws. Since these laws apply to all electric circuits, understanding their fundamentals is paramount in understanding how an electronic circuit functions. Although these laws have immortalised Kirchhoff in Electrical Engineering, he has additional discoveries. He was the first person to verify that an electrical impulse travelled at the speed of light.

The video is here: https://www.youtube.com/watch?v=SYF8HkdZS9w

Kirchhoff’s First Law or Kirchhoff’s Current Law

The total current entering a junction or a node is equal to the charge leaving the node as no charge is lost.

The video is here: https://www.youtube.com/watch?v=SYF8HkdZS9w

Quiz Time

Multiple Choice

Which of the following is the unit for current?

• Volt (V)

• Watt (W)

• Ampere (A)

• Ohm (Ω)

Multiple Choice

What is voltage?

• The amount of electric potential energy per one coulomb of charge
• The amount of 1 coulomb of charge per unit of potential energy
• The number of volts per coulomb
• The amount of electric potential energy per volt

Multiple Choice

In the given current distribution what is the value of I

• 3A

• 8 A

• 2A

• 5A

Multiple Choice

The current in the arm CD of the circuit will be

• $$i_1+i_2$$

• $$i_2+i_3$$

• $$i_1+i_3$$

• $$i_1-i_2+i_3$$

Multiple Choice

Calculate the current at the point A

• 6 A

• 7 A

• 8 A

• 9 A

Multiple Choice

Kirchhoff's 1st law deals with

• current in circuit

• voltage in circuit

• e.m.f in circuit

• voltage in circuit and e.m.f in circuit

Multiple Choice

Current entering and leaving a point in a circuit should be

• equal

• decreasing

• increasing

• variable

Multiple Choice

"The total current in a parallel circuit equals the sum of the individual branch currents."

• Ohm's Law

• Kirchhoff's Voltage Law

• Kirchhoff's Current Law

• Bolen's Law

Multiple Choice

Three resistances 20 Ω, 30 Ω and 60 Ω are connected in parallel, their

combined resistance is given by

• 110 Ω

• 50 Ω

• 20Ω

• 10 Ω

Multiple Choice

Which of the following is the unit for potential difference?

• Volt (V)

• Watt (W)

• Ampere (A)

• Ohm (Ω)

Multiple Choice

Combined resistance of 5 Ω and 10 Ω are connected in series is equal to

• 10 Ω

• 15 Ω

• 20 Ω

• 25 Ω

Multiple Choice

The difference in electrical potential energy between two places is called …………...

• resistance

• friction

• induction

• voltage

Multiple Choice

Two 10 Ω resistors are connected in parallel, their equivalent resistance is

• 5 Ω

• 10 Ω

• 15 Ω

• 0.5 Ω

Multiple Choice

Which of the following is the electric charge that flows around in a circuit?

• Protons

• Neutrons

• Ions

• Electrons

Multiple Choice

Three resistances 2 Ω, 3 Ω and 6 Ω are connected in parallel, their

combined resistance is given by

• 11 Ω

• 5 Ω

• 2Ω

• 1 Ω

Multiple Choice

At which point is the electric field the weakest?

• A because it is the furthest away
• A because the field lines are further apart
• C because the field lines are further apart
• C  because it is the furthest away

Multiple Choice

Two 10 Ω resistors are connected in series, their equivalent resistance is

• 5 Ω

• 10 Ω

• 15 Ω

• 20 Ω

Multiple Choice

A voltmeter can be used to measure ....

• potential difference

• resistance

• electrical energy

• current

Multiple Choice

The current in the resistor X is 2.0 A and the current in the 6.0 Ω resistor is 0.5 A. Calculate the current in resistor Y

• 0.5 A

• 1.5 A

• 2.5 A

• 3.5 A

Multiple Choice

Two, point charges 𝑞₁ = +5.00 𝑛𝐶 and 𝑞₂ = − 3.00 𝑛𝐶 are separated by 35.0 cm.

What is the potential energy of the pair of charges?

• -3.85 X 10^-7 J

• +3.85 X 10^-7 J

• +1.29 x 10² J

• -7.71 x 10¹ J

Multiple Choice

The current in the resistor X is 2.0 A and the current in the 6.0 Ω resistor is 0.5 A. Calculate the resistance of resistor Y

• 6.0 Ω

• 2.0 Ω

• 4.0 Ω

• 3.0 Ω

Multiple Choice

Which of the following is an insulator?

• Aluminium plate

• Rubber eraser

• Copper wire

• Iron nail

Multiple Choice

Calculate the current at the point B

• 6 A

• 7 A

• 8 A

• 9 A

Multiple Choice

Three charges are placed at the corners of an equilateral triangle of side 2.00 𝑚𝑚 as shown below. Calculate the electric potential energy associated with this configuration.

• 8.9 x 10^-4 J

• 4.5 x 10^-4 J

• 8.9 x 10^-6 J

• 2.7 x 10^-4 J

Multiple Choice

Calculate the current at the point A

• 6 A

• 7 A

• 8 A

• 9 A

Multiple Choice

Cells produce electrical energy by converting it from ....

• heat energy

• kinetic energy

• light energy

• chemical energy

Multiple Choice

Calculate the current at the point E

• 6 A

• 7 A

• 8 A

• 9 A

Multiple Choice

Four capacitors are connected in a circuit as shown below. If the voltage across the battery is 30V, then:

a) what is the total charge flowing through the circuit?

b) what is the charge flowing through the first capacitor on the left? (Think about the rules used in series and parallel circuits for charge)

• a) 200 Micro Coulombs

  b) 200 Micro Coulombs

• a) 66.7 Micro Coulombs

  b) 66.7 Micro Coulombs

• a) 200 Micro Coulombs

  b) 66.7 Micro Coulombs

• a) 66.7 Micro Coulombs

  b) 200 Micro Coulombs

Multiple Choice

Current entering and leaving a point in a circuit should be

• equal

• decreasing

• increasing

• variable

Multiple Choice

In the water pipe model of current and potential difference, what does the water pump represent?

• battery

• bulb

• current

• wire

Multiple Choice

Current through each resistor when they are connected in series is

• different

• same

• decreasing

• increasing

Multiple Choice

Three capacitors of capacitances 3μF, 9 μF and

18 μF are first connected in series and then in parallel. The ratio of the net capacitances in series to that in parallel is _____.

• 1:1

• 1:3

• 1:15

• 3:1

• 15:1

Multiple Choice

"The total current in a parallel circuit equals the sum of the individual branch currents."

• Ohm's Law

• Kirchhoff's Voltage Law

• Kirchhoff's Current Law

• Bolen's Law

Multiple Choice

The magnitude of the current is measured with a device called ..

• ammeter

• voltmeter

• dynamometer

• thermometer

Multiple Choice

"The sum of all voltage drops in a series circuit equals the total applied voltage." This is know as what?

• Ohm's Law

• Kirchhoff's Voltage Law

• Kirchhoff's Current Law

• Bolen's Law

Multiple Choice

Which of the following equations is/are a consequence of Kirchhoff’s rules, when applied to the figure below.

• I only

• II only

• III only

• I and II only

• II and III only

Multiple Choice

If the battery produced 12.6 Volts and what would the current flow be for a 6 Ohm resistor?

• 2.1 A

• 3.1 A

• 1.5 A

• 0.3 A

Multiple Choice

Which of the following equations represent the current I in the circuit?

Multiple Choice

How many Volts would we need to produce a current flow of 8 Amps through a 6 Ohm resistor

• 48 V

• 28 V

• 2.5 V

• 0.75 V

Multiple Choice

Consider the circuit shown in the figure below.

a) Apply Kirchhoff’s law to 𝑙𝑜𝑜𝑝 1 to find the current 𝑖₁.

b) Apply Kirchhoff’s law to 𝑙𝑜𝑜𝑝 2 to find the current 𝑖₂.

c) Find the current i₃.

• a) i₁ = -1/2A

  b) i₂ = -1/3A

  c) i₃ = -5/6 A

• a) i₁ = -3/2A

  b) i₂ = -1/3A

  c) i₃ = -5/6 A

• a) i₁ = -1/2A

  b) i₂ = -1/3A

  c) i₃ = -1/6 A

• a) i₁ = -1/3A

  b) i₂ = -1/2A

  c) i₃ = -5/6 A

Multiple Choice

What size resistor would produce a current flow of 5 Amps with a battery voltage of 12.6 volts

• 2.52 ohm

• 1.89 ohm

• 0.39 ohm

• 2.25 ohm

Multiple Choice

Which of the following statements is Kirchoff's first law?

• the sum of the currents entering any junction in an electric circuit must equal the sum of the currents leaving that junction

• the sum of the charges entering any junction in an electric circuit must equal the sum of the charges leaving that junction

• the sum of the emfs entering any junction in an electric circuit must equal the sum of the pds leaving that junction

• none of these

Multiple Choice

A diode is...

• a device that allows the flow of electric current in one direction only

• a device that prevents damage to other components in a circuit

• can produce simple sounds when there is a current in it

• can produce light when there is a current in it

Multiple Choice

A thermistor is a digital sensor that can measure ......

• pressure

• humidity

• pH level

• temperature

Multiple Choice

A smartphone is being charge by 110 V of mains electricity with current of 2 A for 30 minutes.

• 792 KJ

• 3 KJ

• 396 KJ

• 198 KJ

Multiple Choice

The value of electrical power depends on ..

I. current

II. potential difference

III. time

IV. the source of electrical power

• I and III

• I, II and III

• III and IV

• all of the above

Multiple Choice

A solar cell produces electrical energy by converting it from .... energy

• mechanical

• chemical

• light

• sound

Multiple Choice

Which of the elements is not fossil fuel?

• coal

• biomass

• petroleum

• diesel

Multiple Choice

I. solar power

II. petroleum

III. Diesel

IV. Coal

V. Wind power

Which of the above is renewable energy?

• I, II and III

• I and V

• II, III, and IV

• all of them

Multiple Choice

Which of the following is non-renewable energy?

I. Hydroelectricity

II. Tidal power

III. Geothermal energy

IV. Bioenergy

V. Natural gas

• I and II

• none

• all of them

• I, III and IV

That's it for today