-5 summer science experiments-
-01 Electric fan -
Principle : Electric fan refers to a utensil fan that uses wind to get cool in hot weather. It is a device that uses electric drive to generate air flow. The fan configured in the interior is energized and then rotates into natural wind to achieve the effect of cooling. The main components of the
electric fan are: AC motor . Its working principle is: the energized coil rotates under force in the magnetic field.
Because the fan blade has an inclination angle, it is not on a plane. When the fan blade rotates, overcomes the air resistance of and to do work, and the air obtains kinetic energy. The kinetic energy direction is the same as the vertical direction of the inclined surface of the fan blade. The movement of the air is wind.
- 02 Flying out water -
Principle: When we blow air into the bottle mouth, the air pressure in the bottle will become higher and higher. Due to the limited space of the glass bottle, the straw forms an external channel. The air pressure presses the water in the bottle and sprays it outward through the straw.
If you blow the air hard, the air pressure in the bottle will instantly increase, and a strong and fast water column will be sprayed out; otherwise, a weak and slow water column will be sprayed out. From water dragons to high-pressure water guns, although their shapes are very different, they all use the principle of air pressure water spray.
- 03 Homemade thermometer -
Principle : Objects expand when heated and shrink when cold. This is what people often call "thermal expansion and contraction", which is a basic property of objects. Thermal expansion and contraction are caused by the movement of particles (atoms) in the object to change with temperature. When the temperature rises, the vibration amplitude of the particles increases, causing the object to expand; when the temperature drops, the vibration amplitude of the particles decreases, causing the object to shrink.
In this experiment, the temperature of hot water was higher, so the vibration amplitude of the water molecules in the straw increased and the water level rose; the temperature of cold water was lower, so the vibration amplitude of the water molecules in the straw decreased and the water level decreased. The thermometer liquid column also "grows taller" and "gets shorter" because of this principle. The small bottle we made in the experiment, just like a thermometer, measured the water temperature
- 04 Dry Ice Big Explosion -
Principle : Dry ice is a solid carbon dioxide . When it encounters hot water in the basin, it will quickly sublimate (the process of gasification of solids into gas is called sublimation), resulting in a smoky fairyland-like scene.
In the experiment, the bubble water was applied across the edge of the bowl mouth, and then pulled it with a cotton strip soaked with bubble water, forming a sealed bubble film at the mouth of the bowl.
As the carbon dioxide in the pot increases, the bubble film expands and turns into a super large and beautiful hemispherical bubble. When it expands to a certain extent, the bubble film will burst, which will form a stunning dry ice explosion effect.
- 05 Crystal slug -
Principle : In this experiment, the sodium ion in sodium alginate was replaced by calcium chloride in to form a calcium alginate gel, and calcium alginate is insoluble in water, so it can be quickly formed after being punched out of the syringe to make a cute crystal slug.
The explosion laboratory of genius scientists will deliver a simple and interesting scientific experiment to children and parents at 8 o'clock every night; help more than 1 million parents accompany their children to learn science happily, and let their children fall in love with science together! For more exciting content, please follow the WeChat official account: Explosion Laboratory
