The principle of plastic bags filled with water and coins to drive away flies and mosquitoes is because transparent water bags have the function of convex lenses. When light passes through the convex lens, it will definitely change the surrounding light intensity and temperature, and this change just stimulates some sensitive organs of flies, so keep a certain distance from flies.
The refraction of water in the water bag can really drive away mosquitoes and flies, and it is found that purple water is better in the bag. You can try it at home. It is best to fill the plastic bag and make it into a ball. The more transparent, the better the effect.
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Precautions for driving away flies and mosquitoes:
1, there are many flies in summer. If you don't pay attention to the washed food, you will be bitten by flies and pollute the food. If you put a few washed onions on washed fish, meat or bean products, you will avoid the bite of flies.
2, reduce the "smell" emitted by the body, take a bath frequently, keep the skin fresh, and wipe the sweat in time, which can reduce the attraction to mosquitoes.
3. Use less cosmetics such as perfume and skin care lotion in summer.
When going out for activities, try to wear light-colored clothes and socks at the same time, which can reduce the contact between people and mosquitoes and avoid being bitten.
5. Replace the water in vases and aquatic plants in time, thoroughly clean up the accumulated water in air-conditioning trays and flowerpot bottoms, check the floor drains in bathrooms and kitchens, keep the room dry and free of accumulated water, and prevent mosquitoes.