Some simple and interesting physics experiments: blowing balloons in bottles, cups that can catch balloons, cups that can absorb water, bottles that can eat eggs, and bottles that are flat.

1. Blowing balloons in the bottle?

Thinking: why does the balloon blown in the bottle not become smaller when the balloon mouth is loosened?

Materials: large glass bottle, two straws: red and green, one balloon, air pump?

Operation:?

1, use a screwdriver to punch two holes in the bottle cap in advance, and insert two straws in the holes: red and green?

2. Tie a balloon on the red straw?

3. Cover the bottle cap on the bottle mouth?

4. Use a pump to hit the red straw and make the balloon bigger?

5. Release the red straw and the balloon will become smaller immediately?

6. Use a pump and then hit the red straw to enlarge the balloon?

7. Quickly pinch the two nozzles of red straw and green straw?

8, let go of the red straw mouth, the balloon has not become smaller?

Explanation: When the red straw is loosened, the balloon begins to shrink because of the contraction of its rubber membrane. However, after the balloon is shrunk, the air volume in other parts of the bottle is enlarged, and the green tube is closed. As a result, the air pressure in the bottle will be reduced-even lower than that in the balloon. At this time, the balloon will not continue to shrink. ?

Second, the cup that can catch the balloon?

Thinking: Do you gently invert a small cup on the spherical surface of a balloon and then suck it up? ?

Materials: balloon 1 ~ 2, plastic cup1~ 2, thermos bottle1,a little hot water?

Process:?

1、? Blow on the balloon and tie it?

2、? Pour hot water (about 70℃) into about half a cup?

3、? After the hot water stays in the cup for 20 seconds, pour out the water?

4、? Immediately buckle the cup mouth tightly on the balloon?

5? Gently lift the cup with the balloon?

Note: 1. The cup is directly upside down on the balloon, so it is impossible to suck up the balloon. 2. The cup treated with hot water can suck up the balloon because the air in the cup is gradually cooled and the pressure is reduced. ?

Third, the cup that will absorb water?

Thinking: Cover the burning candle with a glass. What happens in the glass after the candle is extinguished? ?

Materials: glass (higher than candle) 1 piece, candle 1 piece, flat plate 1 piece, lighter 1 piece, and water?

Operation:?

1, light the candle and drop a few drops of wax oil in the center of the plate to fix the candle. ?

2. Fill the plate with water about 1 cm high. ?

3、? Buckle the candle upside down with a glass?

4. Observe the burning of candles and the change of water level in the plate?

Explanation: 1. After the air (oxygen) in the glass is consumed, the candle flame goes out. ? After the candle is extinguished, the water level in the cup will gradually rise. ?

Fourth, the bottle that can eat eggs?

Thinking: Why can an egg enter from a bottle smaller than itself? ?

Materials: cooked eggs 1 piece, narrow-mouthed bottles 1 piece, several pieces of paper, matches 1 box?

Operation:?

1, peeled off the shell of the cooked egg. ?

2. Tear the paper into strips. ?

3. Light the note and put it in the bottle. ?

4. As soon as the fire is extinguished, immediately buckle the egg to the bottle mouth and immediately remove your hand. ?

Explanation: 1. The paper has just been burned and the bottle is hot. 2. After the egg is buckled in the bottle mouth, the temperature in the bottle gradually decreases, the pressure inside the bottle becomes smaller, and the pressure outside the bottle becomes larger, so the egg will be squeezed into the bottle. ?

5. The bottle is flat?

Thinking: Can you deflate the plastic bottle without hands? ?

Materials: 2 cups, warm water 1 cup, mineral water bottle 1 piece?

Operation:?

1, put warm water into the bottle, touch the bottle with your hand, do you feel the heat?

2. Pour the warm boiled water out of the bottle and quickly close the bottle lid.

3. Observe that the bottle is slowly deflated. ?

Explanation: 1.? Heat the air in the bottle to reduce its pressure. 2.? Because the air outside the bottle is under greater pressure than the air inside the bottle, the bottle is crushed.

Extended data:

Physics experiment teaching is an important form and method of physics teaching. Generally, it is divided into demonstration experiment, small experiment in class (experiment while talking), group experiment of students and extracurricular experiment. Demonstration experiment is a performance demonstration experiment with teachers as the main operators.

In-class experiments are small experiments operated by students interspersed in the classroom teaching process. Students' grouping experiment is a process in which students use instruments, observe and measure, obtain data, analyze and process data, and summarize conclusions, including confirmatory experiments and exploratory experiments.

References:

Baidu Encyclopedia: Physics Experiment Teaching