-
There must be energy loss, which burns people, and some handles are cooked, and there must be energy loss.
From a scientific point of view, because one position of the person is electrocuted, the other positions of the person are grounded, or contact with other conductors, and finally the ground is connected to form a ground, causing the current to flow through the body, because the human body is a resistor, so heat is generated. and burned the man, and the other burned.
If a person is standing on top of something insulating, such as very dry wood, that does not form a ground with the ground, then the person is fine.
When we were working on the steel structure dome project at the construction site, there were several electricians from Heilongjiang, who connected the 220V wires and never had any electricity, and stood on top of the wooden ladder. Later, I asked them if there was electricity to them. They say it's hemp, nothing else.
-
From the point of electrical energy: people are electrocuted = people are added voltage, (people = a non-constant resistance) The electrical energy from the wire does work on the human body, and there is energy conversion.
From the human body, when electrified, the human muscles will contract uncontrollably or tremble violently, the muscles need energy support for exercise, and sweating... will cause energy loss.
What is the problem and does it make sense? AC 220V, 1000 2000 in the human body, more than 10mA current people can not extricate themselves, more than 50 mA seconds is easy to die.
Needless to say, 380 volts.
You add and I add.
1. The electrical energy passes through the motor, and the magnetic field then becomes mechanical energy, which consumes reactive power.
2. It can be directly converted into heat energy.
3. It can be partially converted into light energy through light bulbs, etc.
4. Magnetic field energy can be generated.
5. Electroplating The battery is charged, and the electrical energy is converted into chemical energy.
-
There are two types of high-voltage electric shocks: one step voltage electric shock and one high voltage arc electric shock.
There are two kinds of low-voltage electric shocks, one is single-wire electric shock, and the other is two-wire electric shock, in short, they are connected with the live wire and form a loop. Hope it helps.
-
A high-voltage electric shock is probably caused by a voltage difference that allows an electric current to pass through, while a low-voltage electric shock is caused by an electric current passing through the human body without a voltage difference.
-
In the case of being hit by electricity. Because the human body is inherently a conductor.
-
The contact voltage is greater than 36 volts.
-
Contact with excess voltage forms a closed circuit.
-
When the voltage exceeds V, this is the safe voltage for the human body.
-
Direct electric shock occurs when the human body is in direct contact with or too close to the live conductors of electrical equipment and lines;
If the insulation of electrical equipment is damaged and leakage occurs, the human body will be exposed to electricity.
Of course, any kind of electric shock is very dangerous!
-
Single-phase electric shock, biphasic electric shock, step electric shock, provided that both feet are on the ground.
-
Normally, greater than 36V is dangerous.
-
When there is water on the body, or when there is a conductor of electricity.
-
One unintentionally, one intentionally.
-
Both. It can be divided into single-wire electric shock and double-wire electric shock.
When the human body directly touches one of the wires of the live equipment, the current flows into the earth through the human body, and this electric shock phenomenon is called single-wire electric shock.
The human body is in contact with a two-phase conductor in a live device or line at the same time, or in a high-voltage system, the human body approaches a two-phase live conductor of different phases at the same time, and an arc discharge occurs, and the current flows from a one-phase conductor through the human body into another phase conductor to form a closed circuit, which is called a two-wire electric shock. In the event of a two-wire electric shock, the voltage acting on the human body is equal to the line voltage, and this electric shock is the most dangerous.
-
There are 2 wires for a total of 2 household power supplies. Neutral and live wires. There is no electricity at the neutral line, and there is electricity at the live wire. There is electricity when the live wire and the ground are connected, consider how many there are, I hope it will help you,
-
It is true that electrons move a small distance, but when a person is electrocuted, the voltage of the two parts of the body is different, forming an electric field. The electrons in the body form an electric current. Of course, the human body has a large number of electrons, such as touch and vision, which are transmitted to the brain and then fed back by the electrons in the body.
-
Electric shock is the consequence of the current flowing through the human body reaching a certain value, because the alternating current frequency is more likely to stop the heart beating, so the same current flowing through the human body is more dangerous when the alternating current is the same size. In order to prevent electric shock, a series of measures are taken to increase the insulation resistance, such as the plastic protection on the outside of the wire. Electrician's shoes worn by electricians.
-
The safe voltage of the human body is 36V, and the safe current is 30 milliamperes, and if it is higher than these, it will be unbearable, that is, it will be electrocuted, and the higher it is, the more dangerous it is.
-
What is an electric shock? Star Awareness Project
-
Wind energy is wind energy, solar energy is solar energy, tidal energy, geothermal energy, nuclear energy, hydrogen energy, etc., which are all new energy.
Kinetic energy and gravitational potential energy, as well as elastic potential energy, are collectively referred to as mechanical energy.
For example, when the ball falls from a height of H, the gravitational potential energy is converted into kinetic energy, and when it is about to land (limit), the kinetic energy reaches the maximum, and then the kinetic energy is converted into gravitational potential energy, and if the energy loss of the ball hitting the ground is not considered, the mechanical energy is conserved.
The elastic potential energy is mostly for springs. For example, a ball comes at a velocity v, squeezes the spring, the kinetic energy is converted into elastic potential energy, and then the spring bounces the ball away, and the elastic potential energy is converted into kinetic energy, and the mechanical energy is conserved in the whole process.
It is only said that mechanical energy is conserved, and mechanical energy is not taken out separately, unless it is to do work for resistance, and then the mechanical energy is lost, and it is not conserved.
It is enough for junior high school physics to know this.
-
In fact, the simple understanding can be as you said, but solar energy is not simply thermal energy, there is also radiant energy, but in classical physics, this is best to say thermal energy, in fact, thermal energy is not something to be hot, using thermal energy, thermal energy can be regarded as the sum of the irregular motion of molecules and the potential energy between molecules, mechanical energy is divided into kinetic energy and potential energy, in the ideal case of classical physics, when there is no external work in a system, the mechanical energy is constant, that is, the sum of kinetic energy and potential energy is constant, and the two are just converted to each other.
Other energies may not be exposed to much in junior high school, such as nuclear energy, electrical energy, and so on.
-
First, mechanical energy includes kinetic energy and potential energy, and any object has mechanical energy and thermal energy.
When we talk about wind energy, we generally refer to the part of energy used for wind power generation, which is kinetic energy, which of course belongs to mechanical energy, and solar energy is thermal energy.
Kinetic energy is the energy that an object has due to its motion, such as a running car.
-
Wind energy is not mechanical energy, and solar energy is not thermal energy. Mechanical energy includes kinetic energy and potential energy (gravitational potential energy, elastic potential energy), you can say that a running car has kinetic energy or you can say that it has mechanical energy, but for an object that is lifted, you can only say that it has mechanical energy (or potential energy) and cannot say that it has kinetic energy. An object at rest has no kinetic energy.
-
Kinetic energy is the energy produced due to the motion of an object. (Kinetic energy is related to the mass of the object and the speed of the object's motion, for example, I don't know if you see the NBA, if Yao Ming and O'Neal run in the same direction at the same speed, because the weight of the shark is greater than that of the giant, the kinetic energy of the latter is greater than that of the former.)
Mechanical energy is the energy that an object has on a macroscopic scale, including kinetic energy and potential energy. For example, kinetic energy, the energy that an object has due to its motion is kinetic energy, the faster the movement, the greater the kinetic energy, and the greater the mechanical energy;
Chemical energy mainly refers to the binding energy between molecules and atoms of chemical substances, which is reflected in the energy released and transformed when a chemical reaction occurs in a substance, such as the chemical reaction of carbon combustion, and chemical energy is converted into light energy and heat energy.
-
The symbol for mechanical power is p, the unit is watts, and the symbol is w.
The formula is: p=w t
The symbol of electrical power is also p, the unit is watts, and the symbol is w.
The formula is: p w t=ui=i 2r u 2 r
-
Power, force, and distance.
Power: Voltage*Current.
-
First of all, 34 can be excluded, because the power is equal and the time is equal, then the work done should be the same, because the power p=fv because s1:s2=2:1, so v1:v2=2:1, and fA:fB is equal to 1:2
2. The power should be the same, because the power formula is p=fv, and if you want to wait, then p also wants to wait If you still don't understand, I can explain it to you.
-
1 Because the power is equal.
In the same time, if the distance ratio is 2:1, the speed ratio is 2:1P=FV, and the traction F ratio is 1:2
Because w=pt, w is equal.
So choose 1, 2nd question, 4
Both traction and speed are equal because p=fv
So the power is equal.
-
Solution: p is the power, p is the pressure.
p=w t=fl t=psl t=pv t=(Note: s is the area, l is the length, and the multiplication is exactly the volume).
-
First of all, look at whether it is safe voltage (less than or equal to 36 volts).
If it is not a safe voltage, both cases will be electrocuted.
In the first case, you will be electrocuted, and if the voltage is very high, it will also lead to death;
The second condition causes fibrillation of the heart fibers, which leads directly to death.
There is also a ground wire live wire is relative, such as household appliances, if the switch is turned on, then the ground wire is the live wire.
After learning Ohm's law of the whole circuit in high school. In junior high school, the physical quantity of "voltage" lagged behind. You can't solve the problem with the general physical quantity of "voltage". To solve the problem, we need to use the physical quantity of "electric potential". The theory of zero electric potential exists, but it cannot be found in practice.
1" is equivalent to a certain voltage, and the current in the circuit depends on the size of the load x. In reality, you can make the current close to 0, yes, but can you make the current in the circuit equal to 0???
So, touch the wires with your hands and don't try it lightly! It's dangerous.
As for live work, such as: equipotential electrician, ground potential electrician, intermediate potential electrician, that is to be special protection.
-
1 No, a single touch of the live wire, the insulation under the foot can not form a path.
2 will, grounding will form a pathway.
-
Under normal circumstances (generally single-phase electricity)1Won't 2It will be high voltage insulators are also unsafe.
Don't touch it if you have nothing to do.
If you have three-phase electricity, you will be electrocuted.
-
Both 1 and 2 will be electrocuted. The human body also has resistance, and touching the fire wire with two hands will form an electric current flowing through the human body. 2 Needless to say, the earth conducts electricity and can drain it.
Hello, the physics of the eighth grade is like this, first the change of the state of matter, not difficult, the mechanics of the eighth grade "Book II" is the pressure about what water, air, and the surface of the earth, etc., and then the third year of junior high school is the royal force of what lever is used, etc., good luck, hope.
Interesting Physics" can be seen.
1.What would happen to our lives if gravity on all the objects on Earth suddenly disappeared? The four students made the following conjectures, one of which could happen was (a). >>>More
1. Try to think that students are very ignorant and have a low ability to acquire knowledge. >>>More
8. A person standing on the ground uses a pulley group composed of two fixed pulleys and two movable pulleys, and forcefully lifts the weight of 2 103 Ox on the ground to a constant speed of 4 meters high, regardless of friction, and the person does 1 104 joules. Seeking: >>>More