In life, we have become accustomed to some familiar items, such as toothbrushes, canvas shoes and utility knifes, which have brought great help to our lives. However, in addition to commonly used functions, these items actually hide some other functions, which many of us do not k

In life, we have become accustomed to some familiar items, such as toothbrushes, canvas shoes and utility knifes, which have brought great help to our lives. However, in addition to commonly used functions, these items actually hide some other functions, which many of us do not know about. These functions seem inconspicuous, but can bring unexpected help. Therefore, we still need to know about them. Let me talk about: 10 interesting secrets hidden behind the things you may not know!

1, holes in the sink

According to the design of the sink, it may have one, two or three holes, but many people do not know what they are for. In fact, the main purpose of this small hole is to prevent overflow when the drain plug is connected and provide an escape channel for the air in the drain pipe. If there is no such hole, the water in the sink will slowly be discharged due to the resistance it exerted to the air escaping from the drain pipe, so the effect is still quite large.

2, blue bristles on toothbrush

Blue toothbrush bristles are not simple for good looks. They also hide secrets you may not know. They can remind us to change the toothbrush. Generally speaking, when the bristles fade and turn white, you can change the toothbrush, because when the bristles begin to wear and fade, such toothbrushes are ineffective for oral health. Data shows that new toothbrush removes up to 30% of plaque than old toothbrushes, protecting gum tissue from wear and tear bristles.

3, the small black dot next to the iPhone camera

As an iPhone mobile phone user, you may have noticed the small black dot next to the back cover camera many times. What is it for? Many people may not know that this is actually an extra microphone. If you look closely, you will notice the microphone's unique comb structure. In addition to these functions, it also helps suppress noise and capture sound at a wider angle to ensure better conversation quality.

4, shoelace holes next to canvas shoes

Young people like to wear canvas shoes, which look particularly fashionable and young, but have you noticed what the shoelace holes next to canvas shoes are used for? Many people may think it is a decoration, but it is not the case. In addition to providing breathable functions for the feet, it is also to make the shoes more firm and not easily slide off the feet, because the original canvas shoes were designed for basketball, and the far-mobilization at that time would tie shoelaces on this small hole next to the shoes.

5, the end of the tool handle

The tool handle we have used. Although it is very convenient, the blade will become dull and not so sharp after being used for a period of time. Some people will directly replace the blade. In fact, it is not so wasteful, because the detachable part of the tool handle at the end of the tool handle is to remove the blunt part of the blade. The operation is also particularly simple. Take the end of the tool handle, place it in the scale position of the blade, and then press it hard, and the blunt part of the blade will be removed.

6, small holes on the lollipop stick

After eating the lollipop, you will find that there is a small hole on the stick, which looks particularly interesting. Some children will even use it as a whistle. Is it really designed to be a whistle? The answer is no, the reason for this is simple. When the melted caramel is poured into the mold, a small part will enter this small hole to ensure that the delicious part does not fall off the stick and plays a solidification role, which many people may not know.

7, bottom of the shopping cart

When we shop in the mall, we will use the shopping cart. So have you noticed that there is an extra part at the bottom of the shopping cart, what is it for? In fact, this design is completely for customers' consideration, not for simple decoration. We can use it to connect the shopping basket and have some extra space, especially when shopping alone. Using this space can help us ineffectively.

8, bathing foam

The foam produced by bathing can not only lubricate the skin, but also play a thermal insulation function because these foams will trap the air. This is a good insulator. The thick and stable layer of these bubbles will heat insulate the top surface of the water, which will slow down the heat escape through the surface through radiation, convection and evaporation. Especially when bathing in winter, the foam can keep the water temperature for longer, making the bath time longer.

9, remove onion flavor

After we cut the onion, the onion smell on our hands cannot be removed for a long time, which is particularly unpleasant. In fact, there is a small trick that can completely solve this problem, that is, rub your hands on the stainless steel. This is not a joke, because according to scientific tests, when the hands touch the stainless steel, the molecules in the steel will bind to the sulfur molecules on your hands, thereby transferring the molecules together with the smell to the metal and falling off our hands.

10, the two zippers on the backpack

Now there are many zipper designs for backpacks, both of which are made of two. Although many people often come into contact with them, they do not know their purpose. In fact, the two zippers on the backpack increase the strength of the bag under the load, and the zippers are not easy to be damaged, which plays a good protective role. In addition, when the two zippers are arranged together, they can also be fixed with a password lock, which plays a very good anti-theft function.