Find out the phenomenon of thermal expansion and contraction in life and explain it

Balloon. It expands because of the heat.

The main phenomena of thermal expansion and cold contraction in life are: water pipe rupture in winter; The pavement will arch upwards; Bought cans are difficult to open; the principle of use of the thermometer; Eggs soaked in cold water are easy to peel and so on. Thermal expansion and contraction refers to the property that an object expands when it is heated and shrinks when it is cold.

Since the motion of particles (atoms) in an object changes with temperature, when the temperature rises, the vibration amplitude of the particles increases, causing the object to expand; However, when the temperature drops, the vibration amplitude of the particles decreases, causing the object to shrink. Substances such as water (below 4°C), antimony, bismuth, gallium, and bronze shrink when heated in certain temperature ranges and expand when cold, which is the opposite of the characteristics of ordinary objects.

The highway should be sawn at intervals to provide space for thermal expansion and contraction. After soaking the unscrewed cap in very hot water for a while, the lid will be easily opened. Put the brewed hot tea on the table top of a regular glass, and the glass will explode!

If the deflated ping pong ball is soaked in hot water for a while, the ping pong ball will come back to life. When the wires are erected in the summer. To sag more.

In winter, it will collapse relatively tightly......Water is not the same as thermal expansion and contraction.

The phenomenon of heat expansion and cold contraction in life:

1. Water pipes burst in winter.

Winter causes water to freeze inside the pipes, and when the water freezes, it becomes larger, and when it is cold, the pipes shrink, so that the pipes burst.

2. The pavement will arch upward, and sometimes the pavement will arch upwards in summer, which is caused by the expansion of the pavement, so there are gaps left on the pavement every other distance.

3. It is difficult to open the canned food bought.

Because the gas is hot during factory production, the gas expands, and the volume of gas inside decreases after cooling, and the atmospheric pressure outside is greater than that inside, so it is difficult to open, and it is easy to open the can by heating it slightly.

4. Thermometer.

The phenomenon of thermal expansion and contraction of solids, liquids and gases affected by temperature; Under constant volume conditions, the pressure of the gas (or vapor) varies according to the different temperatures;

5. Peel the eggs.

When hard-boiled eggs are soaked in cold water, the eggs are easy to peel off, as the result of the different shrinkage of the shell and the egg white.

Example: 1. The hot steamed bun is large and soft, but when it is cold, it shrinks a little and becomes harder.

2. When paving asphalt roads, there will be some gaps in the next section of the road, which is to prevent the asphalt from expanding due to heat and making the road surface bulge under the summer sun.

3. The metal guardrail of the highway should always leave a gap at the joint, which is to prevent the guardrail from expanding and being damaged at high temperatures.

4. The rail is also to a certain length, there must always be a gap, and then extend downward, also because of the thermal expansion and contraction of the rail, if there is no gap, the rail will expand and bulge under the high temperature in summer.

5. In summer, the tires of bicycles, automobiles, motorcycles, and electric vehicles should not be filled with too much gas to prevent punctures caused by gas expansion when the temperature is high.

Standing alone and colluding.

Thermometer (temperature rise, mercury**).

If the ping pong ball is deflated, it will recover if it is scalded with boiling water; In winter, the water bottle stopper can not be pressed too tightly, otherwise the bottle gall is easy to explode; (Cold shrinkage) cement pavement should open a groove every other section, in order to prevent the pavement from being affected by thermal expansion and cold contraction.

In the summer, you can't pump up your bike too much. (thermal expansion).

Thermal expansion and contraction [1] is a basic property of an object, in the normal state, the object expands when heated and shrinks when it is cold. All objects have this property.

Note: Water above 4 will expand and contract, and below 4 will expand and contract. In the case of ice, the density only means that the ice will float on the surface. Substances such as antimony, bismuth, gallium, and bronze shrink when heated in certain temperature ranges and expand when cold. ）

Objects expand when heated and contract when cold. This is due to the fact that the motion of particles (atoms) in an object changes with temperature, and when the temperature rises, the vibration amplitude of the particles increases, causing the object to expand. However, when the temperature drops, the vibration amplitude of the particles decreases, causing the object to shrink.

Objects have the phenomenon of thermal expansion and cold contraction, and we can use this phenomenon to solve some difficulties in daily life.

Principle For general objects, thermal expansion and contraction are established, mainly due to the increase in temperature, the kinetic energy of molecules increases, and the average free path of molecules increases, so it is manifested as thermal expansion and contraction, but there are exceptions, such as water, which does not mean that thermal expansion and contraction are not valid for water!Rather, there are hydrogen bonds in the water, and when the temperature drops, the number of hydrogen bonds in the water increases, causing the volume to increase as the temperature drops!

Example: Water pipes burst in winter,2 Sometimes the road surface arches upwards in summer, which is the road surface swelling. So there are gaps in the road surface at intervals)

3 The cans I bought were difficult to open because the factory was hot and the gas expanded. After cooling, the volume of gas inside decreases, and the atmospheric pressure outside is greater than that inside. So it's hard to open, and my door can be easily opened with a slight heat can.

4 thermometer 5 high-voltage wires sag a lot in summer and tighten in winter.

Hot air ballooning too.

The above 1 is just an explanation, not an application.

The thermometer of 4 refers to the expansion thermometer.

and when building railways and bridges, it is necessary to leave a space to avoid the damage of thermal expansion and contraction, which is a negative application.

Broken water pipes in winter: In winter, water freezes in the pipes, and the water freezes in size, and when it is cold, the pipes shrink and burst. The pavement will arch upwards;

Sometimes in the summer, the road surface arches upwards because the road surface swells, so there are gaps in the road surface at intervals. The bought cans are difficult to open: because the factory is hot during production, the gas expands, and the volume of the gas inside decreases after cooling, and the atmospheric pressure outside is greater than the inside, so it is difficult to open, and the cans can be easily opened by heating a little.

1. Broken water pipes in winter: In winter, the water will freeze in the water pipes, and the volume of the water will become larger after freezing, and the water pipes will shrink when it is cold, and the water pipes will burst.

2. The pavement will arch upward: Sometimes the pavement will arch upwards in summer, which is caused by the expansion of the pavement, so there are gaps left on the pavement every other distance.

3. It is difficult to open the canned food bought: because the factory is hot during production, the gas expands, the volume of gas inside decreases after cooling, and the atmospheric pressure outside is greater than that inside, so it is difficult to open, and the cans can be easily opened if they are heated slightly.

4. Thermometer: the phenomenon of thermal expansion and contraction of solids, liquids and gases affected by temperature; Under constant volume conditions, the pressure of the gas (or vapor) varies according to the different temperatures;

5. Peel eggs: Soak hard-boiled eggs in cold water, and the eggs will be easy to peel, which is the result of the different shrinkage of eggshells and egg whites.