What can be cooked from squid: quick and tasty

"Electric current in gases" - In the world industry, about 90% of tool steel is smelted in electric arc furnaces. Arc discharge. Types of self-sustained discharges. Glow discharge. Electric current in gases. Electric current in gases Discharges and types of discharges in gases. Corona discharge is accompanied by a faint glow and little noise.

"Electric Current Problems" - Quiz. Current work. Terminological dictation. The purpose of the lesson: Basic formulas. First level tasks. Physics lesson: generalization on the topic "Electricity". Tasks. Voltage. Electricity. Second level tasks. Current strength. Resistance. 2. There are two lamps with a power of 60 W and 100 W, designed for a voltage of 220V.

"Electric current in metals" - What is electricity? Table of contents. The diagram of the Tolman and Stewart experiment is shown in the figure. Superconductivity. The total charge flowing through the circuit was measured by the rejection of the galvanometer needle. Potential barrier. Superconductivity is observed not only in elements, but also in many chemical compounds and alloys.

"Direction of electric current" - Action of the current. The electric current has a certain direction. So, the magnetic needle near the conductor with current turns. Electricity. The ordered (directed) movement of charged particles is called electric current. If the current strength does not change over time, then the current is called constant.

"Lesson Electric Current" - The disorderly movement of free particles. U is the voltage. I got it. S - area cross section, units R- resistivity substances, units measurements. Conductor resistance depends on: L - conductor length, unit. measurements 1m. Measurements 1m2. The movement of free particles under the influence of an electric field.

"Electric current action" - Formulate a hypothesis about the expected action of the current. (Kant Immanuel is a German philosopher, 1724 - 1804). Select the equipment for the experiment on the demonstration table according to the picture. Draw a circuit diagram. What is the source of the Earth's magnetic field? Run the experiment. A minute of rest. "Report-story".

Electrical safety and the effect of electric current on the human body. Completed by: Koop A. Electrical safety

Electrical safety is a system of organizational and technical measures and means to protect people from harmful and dangerous effects of electric current, electric arc, electromagnetic field and static electricity.

Types of exposure to electric current

The nature of the electric shock and its consequences depend on the value and type of current, the path of its passage, the duration of exposure, the individual physiological characteristics of a person and his condition at the time of injury.

Biological

Thermal

Electrolytic

There are the following types of exposure:

Types of electric shock

Burns
Leather metallization
Electrical signs
Electrophthalmia
Electric shock
Mechanical damage

Electrical burns

An electrical burn may not seem too severe or leave no marks on the skin at all, but it can cause damage to tissues deep under the skin. Passing a strong electric current through the body can cause malfunction of internal organs, such as irregular heartbeat or cardiac arrest.

Leather metallization

Metallization of the skin - penetration into its upper layers of the smallest particles of metal melted under the action of an electric arc. This occurs mainly during short circuits, when disconnecting switches and circuit breakers under load, etc. The damaged area of the skin has a rough, hard surface. The color of the affected area usually resembles the color of the metal, parts of which penetrate the skin. At the same time, the victim experiences skin tension from the presence of a foreign body in it, as well as painful sensations from a burn due to the heat of metal brought into the skin (melting of a metal particle has enough high temperature- several hundred ° C).
Metallization of the skin is observed in about 10% of victims. In most cases, simultaneously with the metallization of the skin, an electric arc burns occurs, which almost always causes more severe injuries.

Electrical signs

Electrical signs on the human body arise as a result of chemical or thermal (up to 110-115 ° C), as well as the combined chemical and thermal effects of an electric current. Typically, sharply outlined gray or pale yellow marks are round or oval in shape. There are also signs in the form of lines and small-dot tattoos. Sometimes the shape of the sign corresponds to the shape of the live part touched by the victim. The affected area of the skin hardens, death of the upper layer of the skin occurs.
As a rule, electrical signs are painless and their treatment ends safely: over time, the top layer of the skin comes off and the affected area acquires its original color, elasticity and sensitivity.
Electric signs are quite common: they occur in about a fifth of those affected by electric current.

Electrophthalmia

Electrophthalmia. When an electric arc occurs, which is a source of intense radiation of ultraviolet rays, as a result of irradiation of the eyes, after a while (2-6 hours), inflammation of the outer membranes of the eyes occurs. This disease is called electrophthalmia. In severe cases of eye damage caused by exposure to a powerful stream of ultraviolet rays, eye treatment can be difficult and time-consuming.

Electric shock

An electric shock, as already defined above, is the excitation of living tissues of a person caused by an electric current flowing through it and accompanied by involuntary convulsive muscle contractions.

Mechanical damage

Mechanical damage is the result of sharp involuntary convulsive muscle contractions under the action of a current passing through the human body. As a result, ruptures of the skin, blood vessels and nerve tissue, joint dislocations, and bone fractures can occur. Of course, these injuries do not include similar injuries caused by a person falling from a height, bruises on objects and similar cases, which can also occur with electric shock.

By the effect of currents are:

Tangible
Unreleasing
Fibrillatory

Perceptible currents

Perceptible currents are currents that cause perceptible irritations when passing through the body. A person begins to feel the effect of alternating current (50 Hz) at values from 0.5 to 1.5 mA and constant from 5 to 7 mA. Within these limits, there is a slight trembling of the fingers, tingling, heating of the skin (DC).

Non-releasing currents

Unreleasing currents cause convulsive muscle contraction. The smallest value of the current at which a person cannot independently tear his hands off the live parts is called the threshold non-releasing current. For alternating current, this value lies in the range from 10 to 15 mA, for direct current - from 50 to 80 mA

Fibrillation currents

Fibrillation currents cause cardiac fibrillation - flutter or arrhythmic contraction and relaxation of the heart muscle. As a result of fibrillation, blood from the heart does not enter the vital organs and, first of all, the blood supply to the brain is disrupted. The human brain, deprived of blood supply, lives for 5-6 minutes, and then dies.
The value of fibrillation currents ranges from 80 to 5000mA.

Clinical death

Clinical death is a reversible stage of dying, a transitional period between life and death. At this stage, the activity of the heart and respiration stops, all external signs of the body's vital activity completely disappear. At the same time, hypoxia (oxygen starvation) does not cause irreversible changes in the most sensitive organs and systems. This period on average lasts no more than 3-4 minutes, maximum 5-6 minutes.
The shorter the period between the declaration of clinical death and the beginning of resuscitation measures, the more chances of life for the patient, therefore, diagnosis and treatment are carried out in parallel.

Biological death

Biological death (or true death) is an irreversible cessation physiological processes in cells and tissues. Irreversible termination is usually understood as “irreversible in the framework of modern medical technologies” termination of processes. Over time, the possibilities of medicine to resuscitate deceased patients change, as a result of which the border of death is pushed back into the future.

Depending on the outcome of the defeat, electric shocks can be conditionally divided into the following four degrees:

I - convulsive muscle contraction without loss of consciousness;
II - convulsive muscle contraction with loss of consciousness, but with preserved breathing and heart function;
III - loss of consciousness and impaired cardiac activity or breathing (or both together);
IV-lack of breathing and blood circulation, i.e. death.

The nature of the lesion is determined by:

Time of action of current
Individual physiological characteristics of a person (physical health, the presence of diseases of the cardiovascular system, skin, nervous system, the presence of alcohol in the blood)

Two-phase switching on of a person Single-phase switching on of a person Paths of current passage The path of current passage has a significant impact on the nature of the lesion. The most dangerous is the path through the head and spinal cord, heart, lungs. As the analysis of electrical injuries shows, the paths of passage of the current "right hand - legs", "hand - hand" are found most often, the paths "head - legs", "leg - leg" are less common.

Slide 1

The effect of electric current on a person.
Completed: 9th grade student Bakovskaya Julia Checked by: physics teacher Tsipenko L.V. 2011

Slide 2

How does electric current affect a person?
The fact of the effect of electric current on a person was established in the last quarter of the 18th century. The danger of this action was first established by the inventor of the electrochemical high-voltage voltage source V.V. Petrov. The description of the first industrial electrical injuries appeared much later: in 1863 - from direct current and in 1882 - from alternating current.

Slide 3

Electrical traumatism is characterized by the following features: a protective reaction of the body appears only after a person gets under voltage, that is, when an electric current is already flowing through his body; electric current acts not only in the places of contact with the human body and on the path of passage through the body, but also causes a reflex action, manifested in the disruption of the normal activity of the cardiovascular and nervous system, respiration

Slide 4

There are two types of electric shock to the body: electrical injury and electrical shock.
Electrical injuries are local injuries to tissues and organs: electrical burns, electrical signs and electrometallization of the skin. Electric burns occur as a result of heating of human tissues by an electric current of more than 1 A flowing through it. Burns can be superficial, when the skin is affected, and internal ones, when deep-lying tissues of the body are affected. According to the conditions of occurrence, contact, arc and mixed burns are distinguished.

This presentation acquaints students with safety rules in handling electricity, electrical appliances, warns against accidents in everyday life.

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"Lesson on OBZh.Selivanov"

OBZH lesson

Selivanova Svetlana Anatolyevna

Primary classes

"Electricity"

Target:

Familiarization of students, pupils with the rules of using electrical appliances.

Tasks:

To expand the knowledge of students about the variety of electrical appliances used in everyday life.

Introduce the rules for using electrical appliances.

Develop logical thinking.

To develop skills in working with information.

Course of the lesson

Experiment.

If you rub a pencil on a piece of woolen cloth, then bring it to the small pieces of paper laid on the table, we will see…. What is this phenomenon?

(electricity action)

Topic message.

The word "Electricity" - Greek word and means amber. Even in ancient times, the Greek mathematician Thales had an idea of electricity. Rubbing an amber stick on wool, he charged it with static electricity. Brought to the head, this stick attracted the hair. We got this electricity ourselves.

But this electricity is called static because it only accumulates in various objects. It cannot be transmitted over a distance and cannot be used in lighting fixtures.

Later, scientists found that electricity is a stream of tiny charged particles - electrons. Each electron carries a small charge of energy. But when there are a lot of electrons, the charge becomes large and an electric voltage arises. This is why electric currents can travel long distances through wires.

Independent work in groups. Find the answer to the question:

How does electricity come to your home?

Story(handouts on tables)

To transfer electricity to where it is needed, power lines are being built. You, of course, saw high pillars beyond the settlement - supports, to which the wires are suspended. These wires carry electricity from power plants to different cities and towns.

Electricity flows through the wires under very high voltage reaching hundreds of thousands of volts.

So that no one can even accidentally touch the wires, they are hung high in the sky on special supports. And so that lightning does not strike the wires, a special wire is hung over them - lightning rod.

You can see it at the very top of the support.

When electricity enters the city through wires, it goes to electrical substation. There is a special car - transformer.

Never touch a cable that is sticking out of the ground, as it may carry high voltages!

Electricity comes through cables to the transformer box, which stands near the houses in your locality... A small transformer in it lowers the voltage even further, so that now electricity can be used in various appliances that are in your home.

How does electricity come to your home?

Why are the supports so high?

What rule did you learn from reading the story?

(Discussion.)

What appliances in your home can use electricity?

Crossword "Electrical devices"

Only me, only me

I'm in charge of the kitchen.

Without me, how do not work,

Sit back without lunch. (electric stove)

He willingly breathes dust,

Does not get sick, does not sneeze. (vacuum cleaner)

On the table, in a cap,

Yes in a glass vial

A friend settled -

Cheerful light. (lamp)

Look at my barrel

A top is spinning in me

He doesn't hit anyone,

The cream will quickly knock you down. (mixer)

They pull themselves apart from each other

Not a radio, but says

Not a theater, but a show. (television)

What is the keyword that came out? (dangerous)

When you press the switch of a lamp or some device, the electric current coming from the generator begins to flow through the wires and the device begins to operate, and the light bulb glows.

If the wires are faulty, the electricity becomes dangerous. A person can accidentally touch a bare wire and get an electric shock. Wires can connect and a short circuit or even fire will occur.

Therefore, if you see a bare wire or a faulty switch, an outlet, immediately tell an adult about it.

Anything that runs on electricity must be in good working order!

If it smells burnt from the TV or vacuum cleaner, if sparks are visible, you must immediately unplug the wire. Such a device needs to be repaired.

Can you repair faulty electrical appliances yourself?

You need to know how to handle electricity!

What should not be done under any circumstances?

Remember, electricity doesn't like being near water.

Discussion of pictures on slides. (We draw conclusions ourselves)

There are several electrical appliances on the table.

Consider them carefully and determine which electrical appliances cannot be used.

(discussion)

Bottom line.

Let's repeat again with what rules for using electrical appliances.

What have we learned about electricity?

Why is it dangerous? How to avoid the trouble of interacting with electricity?

Reflection

Today at the lesson I (me)….

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"Electricity. Selivanova"

MS (C) OU "B-Usinskaya special (correctional) boarding school of the 8th type"

Primary classes

S.A. Selivanova

How do electrical appliances work?

I run along the paths, Without a path I can not. Where are I guys not, The light in the house will not light up To distant villages, cities Who goes along the wires? Bright Majesty This is ELECTRICITY!

The bubbling water flows in the river

Electric current flows through the wires.

Goes, runs, flies to help us

Cook lunch, vacuum the floor, the sofa.

Electricity is supplied to electrical appliances using a socket and a plug

IRON

Strokes everything that it touches

And if you touch it, it bites.

A very necessary friend in life -

Electric iron!

Dry wind dries my mother's curls.

FRIDGE

Admire, look:

North Pole inside

Snow and ice are sparkling there

Winter itself lives there.

Forever us this winter

Brought from the store.

ELECTRIC KETTLE

Boils from the inside And blows bubbles.

Enjoy the evening with Tasty Brewed Tea!

TELEPHONE

He runs along the wires -

Tell me here

And you can hear it there.

TELEVISION

I look at the screen in the apartment, And I see what is happening in the world.

Weather, news, movies,

I learn about sports at the same time.

WASHER

Required item

we have it, It works quietly,

it pleases the eye. It will save time

and save your hands - Washing machine

will save us from worries!

VACUUM CLEANER

We have a robot in our apartment, -

He has a huge trunk.

The robot loves cleanliness,

And it buzzes like a liner: "Tuu-u".

Eagerly swallows dust,

But he does not get sick, does not sneeze.

ELECTRIC STOVE

Four red suns

I have in my kitchen

Four red suns

Burned and went out.

Borsch, pie, pancakes are ready.

Until tomorrow the sun is not needed.

MICROWAVE BAKE

Cooking quickly, dexterously -

I need a microwave. Tink! Here is delicious food

Cooking quickly, easily!

RECORD PLAYER

My friend is with me

lives side by side.

Press the button -

and he will sing a song.

FAN

With this fast propeller He gives us a fresh wind! And the air will become fresher For all people, for all children!

Solve the crossword puzzle

Electricity dislikes:

METAL

ITEMS

Look closely at the drawing.
Make a conclusion.

Do not use defective electrical appliances.
You cannot repair, disassemble electrical appliances yourself.
Do not pick at the outlet with your finger or other objects.
Do not turn on electrical appliances with wet hands.
Bare wires should not be touched.

Today at the lesson I (me)….

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