Thinking: Insert a chopstick into a cup filled with rice and lift it. Chopsticks can lift rice and cups.
Up?
Materials: a plastic cup, a rice cup and a bamboo chopstick.
Operation:
1. Fill the plastic cup with rice.
2. Press the rice in the cup by hand.
3. Hold the rice with your hands and put chopsticks between your fingers.
4. Gently lift chopsticks with your hands, and the cup and rice are lifted together.
Explanation:
Due to the extrusion between rice grains in the cup, the air in the cup is squeezed out, and the pressure outside the cup is greater than the pressure inside the cup.
Pressure makes chopsticks and rice grains closely combined, so chopsticks can lift the cup into the rice.
Bottle race
Thinking: two bottles of equal weight, one full of sand and the other full of water, roll down from a height, who will reach the finish line first?
Point?
Materials: two bottles of the same size and weight, sand, water, a rectangular board and two thick books.
Operation:
1. Make a slope with a rectangular board and two books.
2. Pour water into another bottle and sand into the bottle.
3. Put two bottles on the board and let them roll down at the same starting height at the same time.
The bottle filled with water reaches the finish line earlier than the bottle filled with sand.
Explanation:
The friction between sand and the inner wall of the bottle is much greater than that of water, and there will be friction between sand.
Shit, so it's slower than a water bottle.
Creation: change the substances in the bottle and let them compete!
Paid newspaper
Thinking: Without glue, tape and other things, newspapers can stick to the wall without falling off. You know this is
Why?
Material: 1 pencil; 1 newspaper.
Steps:
1. Spread the newspaper and lay it flat on the wall.
2. After a few quick rubs on the newspaper with one side of the pencil, the newspaper won't fall off like sticking to the wall.
Yes
3. Lift a corner of the newspaper, and then let go, and the lifted corner will be sucked back by the wall.
Take the newspaper off the wall slowly and pay attention to the static sound.
Description:
1. Wipe the pencil to charge the newspaper.
2. The charged newspaper was sucked to the wall.
When the air in the room is dry (especially in winter), if you take the newspaper off the wall, it will
Hear the crackle of static electricity.
Creation: Please have a try. What else can be stuck to the wall by static electricity without glue?
Separation of pepper and salt
Thinking: I accidentally mixed the kitchen spices: pepper and salt, how to divide them.
What about driving?
Ingredients: pepper, salt, plastic spoon, small dish.
Operation:
1. Mix salt and pepper.
2. Stir well with chopsticks.
3. Rub the plastic spoon on the clothes and put it on the salt and pepper.
4. Pepper sticks to the spoon first.
5. Move the plastic spoon down slightly.
6. After salt, stick it on the spoon.
Explanation:
Pepper is electrostatically adsorbed earlier than salt because its weight is lighter than salt.
Create:
Can you separate other mixed materials in this way?
Inflatable balloon
Thinking: When will two balloons attract each other and repel each other?
Material: 2 inflatable balloons, 1 string, 1 cardboard.
Operation:
1 Inflate two balloons separately and tie a knot in your mouth.
Connect two balloons with a thread.
Rub the balloon on your hair (or sweater).
Lift the middle part of the rope and the two balloons will separate immediately.
Put the cardboard between two balloons, and the electricity on the balloons makes them attracted to the cardboard.
Explanation:
The electricity on one balloon repels the electricity on the other balloon.
The electricity on the two balloons attracts them to the cardboard.
Creation: Can other small experiments be used to illustrate that balloons are charged?
Lovely watermark
Thinking: The beautiful patterns on rice paper are not drawn, but how are they made?
Materials: 1 washbasin, 1-2 rice paper, 1 chopsticks, 1 cotton swab, 1 bottle of ink and water (about half a basin).
Operation:
1, pour half a basin of water into the washbasin, gently touch the water surface with chopsticks dipped in ink, and you can see that the ink is in the water.
The surface expands into a circle.
2. Wipe the scalp with a cotton swab for two or three times.
3. Then touch the center of the ink circle and see what happens.
4. Gently cover the calligraphy paper on the water, and then pick it up slowly. What patterns are printed on the paper?
Explanation:
1. When the cotton swab touches, the ink will swell into an irregular circular pattern.
2. A small amount of oil on the scalp rubbed by cotton swabs will affect the mutual pulling force of water molecules.
3. The watermark will present irregular concentric circles.
Create:
Try other methods to change the ink pattern on the water surface.
How to write the primary school science experiment report? Write in the middle: XXX test report, write the name on the left and the time on the right; Then write down: 1, ask questions, 2, guess, 3, test equipment, 4, test steps, 5, observe phenomena, 6, conclusion.
Primary school science experiment report: color and heat absorption! Color and heat absorption of objects
The question arises:
On Sunday morning, my mother and I hung our clothes on the balcony. Mom picked up Dad's two clothes-a slightly thick black coat and a thin white shirt, and asked, Do you want to air the black clothes or the white shirt first? I compared the thickness of these two clothes and said without thinking, of course, the white clothes did it first.
At about 3: 30 in the afternoon, I ran out of the balcony and touched two clothes respectively. Unexpectedly, I found that the thick black clothes were all dry, and the white shirt was not dry enough. What's going on here?
Guess and analyze:
The drying of wet clothes is actually the process of water absorption and evaporation. Black clothes dry first, which means that black clothes absorb more calories than white shirts. But black clothes dry before white clothes. Could it be that the color of the object is related to the heat absorbed?
Design and testing:
Experiment 1: I took out two pieces of cloth with the same texture and thickness from the warehouse-one is white and the other is black. Put them in the same basin of water at the same time, soak them and pick them up at the same time, screw them together and wring the water (let them keep the same amount of water), then hang them on the balcony and dry them at the same time.
Measurement results: (When drying, the fabric changes as follows)
10 minutes, 20 minutes, one hour, two hours and three hours
The white cloth stopped dripping, wet and slightly dry. The upper part is dry and the lower part is not dry.
The black cloth is no longer wet. The upper part of a pile of steam is obviously dry, most of it is dry, and the bottom edge is still wet and completely dry. It is obvious that the cloth is getting hot.
From this, I can confirm that the soaked black cloth dries earlier than the white cloth under the same conditions. That is, the heat absorption capacity of black cloth is stronger than that of white cloth.
Emerging new problems:
The heat absorption capacity of black cloth is stronger than that of white cloth. What about the heat absorption relationship of other objects?
Experiment 2: I borrowed a thermometer from the laboratory, took two identical black and white boxes from home, filled some water in the boxes, and opened a hole in the top of the boxes, just to let the thermometer stick in. The experiment was conducted on the top floor:
measuring object
Time and temperature (℃) Water in black paper box and water in white paper box.
Go to 19 19
After 2 minutes, 2 1 19.5
Four minutes later, 22.5 20
Six minutes later, 24 20
Eight minutes later, 26 20
10 minutes later 26 2 1
15 minutes later 28 22.5
Twenty minutes later, at 29: 23.
According to the measurement results, I found that the water temperature in the black paper box rose rapidly, rising by 10℃ in 20 minutes, while the water temperature in the white paper box rose slowly, only rising by 4℃ in 20 minutes. Combining the above two experiments, I think that black objects have stronger heat absorption ability than colored objects, that is, black objects have stronger heat absorption ability than white objects.
A new question arises: Are the heat absorption capacities of other colors the same except black and white? So, I went on to do the following experiment:
Experiment 3: I added 100mL of red, yellow, blue, green and purple water made of pigment and water into five identical glasses, and with the help of my sister, I put five glasses on the platform, and after a certain period of time, I measured the temperature of the water in various colors with a thermometer.
Time and temperature of the measured object (℃) Red water, yellow water, blue water, green water and purple water.
At the beginning,19191919.
10 minutes later 23 22.5 2 1.5 23
15 minutes later, 25 24 25 24 25
After 20 minutes, 26.5 25 26 25.5 27
25 minutes later 27.5 26 27 26 27.5
After 30 minutes, 28.5 27 28 27 28.5
According to the experimental results, I think different colors of water have different heat absorption ability in the sun, and I also find that the deeper the color, the stronger the heat absorption ability.
Conclusion: After nearly a week of experiments, I have come to a conclusion that the heat absorption capacity of an object is related to its color, and the darker the color, the stronger the heat absorption capacity.
The basic requirement for the difference between the original record sheet and the experimental report sheet of primary school scientific experiments is: 1. The original records of the experiment must be recorded in the official experiment record book, and bound with page numbers; There must be continuous page numbers, and pages cannot be missing or patched. 2. The first page of the experiment record book is generally used as a directory page, which can be filled in after the experiment begins or ends. 3. Each experiment should be carried out in the order of year, month and day.
Report on the primary school scientific simulation experiment of cactus evaporation. Hello, I read your description. What's the problem?
If you don't describe the question clearly, it will be difficult for people to answer the question and help you.
I hope you can describe the questions you want clearly as soon as possible, so that everyone can answer them as soon as possible and help you. Thank you.
Is the primary school science experiment report filled out by teachers or students? What would happen if the teacher asked students from other grades to fill it out! What will happen if I report it to the Education Bureau? What can I say?
Primary school science experiment teaching plan experiment content: measure 1 minute breathing and heartbeat times.
Lesson 3, Unit 4, Book 1, Grade 4, Science and Education Edition "What will happen if you jump (1)"
Instructor: Lei Yiwu's teaching time: 20 1 1-4- 17.
SETTING: Sichuan Kaijiang Changling Central School.
Topic: What happens when you jump?
Objective: Through experiments, we realize that exercise affects our breathing and heartbeat, and heartbeat is related to breathing and exercise.
Key points of the experiment: knowing that exercise can make people's breathing and heartbeat accelerate rapidly, and breathing and heartbeat will gradually return to normal after rest.
Difficulties in the experiment: Learn to measure your breathing and heartbeat correctly.
Experimental equipment: self-made multi-channel demonstration and diagnosis stethoscope with stopwatch and self-made breathing counter.
Type of experiment: demonstration experiment and student operation.
Key points of experimental steps
Breathing and heartbeat were measured in a quiet state for 65,438+0 minutes. The teacher demonstrated the multi-channel demonstration of the combined diagnostic stethoscope with a stopwatch, measured the heartbeat, and emphasized the importance of determining the position of the heart (the heart is located on the left side of the human chest).
2. Guide the correct use of stopwatches. Time should be accurate.
3. Students were divided into groups and measured the heartbeat of 1 min in a quiet state with a multi-channel demonstration stethoscope with a stopwatch. The students measured each other well. Three or five students can listen at the same time.
4. Remind the attention points of measuring the number of breaths: take a breath and breathe. When people breathe, the nasal cavity, chest cavity, abdominal cavity and other organs all participate in activities, and the body changes obviously, and students can also feel it. Demonstrate the measurement of breathing time with a self-made breathing counter. Don't be nervous, keep breathing evenly and smoothly, and don't take deep breaths on purpose. )
5. Students are divided into groups to measure their breathing at 1 min in a quiet state. In pairs.
6. Record the data in the record table when measuring.
Breathing and heartbeat were measured 1 min after exercise, and exercise for 2 minutes.
The heartbeat and respiration of 1 min were measured immediately after 2.2 minutes of exercise. Breathing and heartbeat can be measured at the same time.
3. Students measure in groups, and record data in the record table when measuring.
4. Measure the heartbeat and the number of breaths per minute after rest.
The experiment summarizes the experimental data and finds that the heartbeat and breathing at rest are different from those after exercise. When people exercise, they need to consume much more energy than before, so the number of breaths and pulse beats will increase. Everyone's breathing and heartbeat are different, but generally they breathe about 20 times and their heartbeat is about 80 times.
4. Organize equipment and experimental data.
Experimental conclusion: In general, students breathe about 20 times per minute and their heart beats about 80 times. Exercise makes the heart beat and breathing faster. Breathing and heartbeat will gradually return to normal after rest.
Reflection after the experiment: Before the experiment, students knew less about their bodies than I thought. When students are asked to predict their breathing and heartbeat time in one minute, the difference in numbers is incredible. Prediction is not groundless, but must be based on your original knowledge and experience. Although students have been specially trained in measurement skills since the third grade, for a long time, learning divorced from real life still makes students feel strange about numbers.
"I have to breathe about 60 times a minute." "My heart beats about a dozen times in 1 minute!" "100 times!" "Thirty times!" ..... Faced with these figures, I really feel that children's understanding is quite different, and it also makes me realize how important it is to carry out quantitative education for students.
After the experiment: I underestimated the wisdom of the students again. "It's cold, and the clothes we wear are thick. It's troublesome to feel the heart, and sometimes we may not feel it." By touching the pulse of the wrist, we can know the beating times of the heart by measuring the beating times of the pulse. I also found that not only breathing and heartbeat times will increase after exercise; When crying, angry, nervous in exams, wronged when walking at night, scared, doing something wrong, scared by others,,, and so on can increase the number of breaths and heartbeats.
One-minute breath heartbeat record
After two minutes of exercise in a calm state, it takes a long time after exercise.
One-minute call
Inhalation times
The number of heartbeats in one minute
Primary school science experiment report
Fourth grade 1 class experimenter of kaijiang Changling central school.
Time: 20 1 1-4- 17 experimental name: respiration and heartbeat measurement.
Experimental equipment: multi-channel demonstration and consultation stethoscope with stopwatch, breath counter.
I guess: exercise affects our breathing and heartbeat. The more exercise, the more oxygen we consume, so we need to speed up the breathing in the lungs to absorb more oxygen.
Here's what I did: 1. Measure the heartbeat with a multi-channel demonstration consulting stethoscope with a stopwatch, and determine the position of the heart (the left side of the human chest) under the guidance of the teacher.
2. Learn to use stopwatch correctly and keep accurate time.
3. Use a multi-channel demonstration consulting stethoscope with a stopwatch to measure your own heartbeat 1 minute in a quiet state, and students can measure each other. Three or five students listen together.
4. Measure the breathing time of 1 min with a breathing counter.
Observed phenomena: two minutes after exercise in a calm state, and a long time after exercise.
Breaths per minute 20 32 25
The heart rate in one minute is 85 108 90.
I think: under normal circumstances, breathing is mostly 25 times per minute, and the heartbeat is 80 times; Exercise makes the heart beat and breathing faster. Breathing and heartbeat will gradually return to normal after rest.
Problem: When climbing a tall building, some students will be panting, but some students' breathing will not change much.
Instructor: Lei Yiwu Rating:
Design of Inquiry Activity of "Measuring Breath and Heartbeat" in Primary School Science
Lesson 3, Unit 4, Book 1, Grade 4, Science and Education Edition "What will happen if you jump (1)"
Instructor: Lei Yiwu's teaching time: 20 1 1-4- 17.
SETTING: Sichuan Kaijiang Changling Central School.
The teaching of this course mainly consists of three parts:
First, by guiding students to recall their physical changes before and after participating in sports, and talking about their feelings after sports, we can stimulate students to pay attention to the influence of sports on their breathing and heartbeat, and understand their original understanding of the influence of sports on their breathing and heartbeat.
Second, organize students to collect the data of breathing and heartbeat per minute in three States (static, after exercise and after resting for 3 minutes). In this process, the guidance before measurement is very important. Do you want students to guide you to play? When measuring data, the accuracy of the data is the most important. Therefore, students should be organized to discuss "How can we make our measured breathing and heartbeat times more accurate?" The measurement method and matters needing attention in measurement are discussed in detail.
Thirdly, organize students to use statistical charts to analyze the three groups of data collected, and guide students to discover the laws of breathing and heartbeat, as well as the influence of exercise on breathing and heartbeat.
First, teaching objectives: scientific concepts:
1. Know your breathing and heartbeat times under normal conditions and after exercise;
2. Realize that exercise affects our breathing and heartbeat, and heartbeat is related to breathing and exercise.
3. The human body needs oxygen for exercise, and the gas exchange in the lungs sucks oxygen into the blood and excretes carbon dioxide.
4. The more exercise the human body does, the more oxygen it consumes, so it is necessary to speed up the breathing in the lungs to absorb more oxygen.
5, regular exercise can increase the body's vital capacity, which is conducive to good health.
Second, the process and method: scientific inquiry:
1, which can accurately measure the number of breaths, heartbeats and pulses within 1 minute when you are calm, after exercise and after resting for 3 minutes after exercise;
2. Be able to analyze the collected data by using the learned mathematical methods;
3. Be able to explain the problem to be studied by analyzing the data;
Third, emotional attitudes and values:
1, willing to communicate with classmates, able to cooperate to complete experimental activities.
2. Be able to measure the heartbeat and breathing times patiently and meticulously.
3. Recognize the importance of the accuracy of collecting scientific data;
Fourth, the teaching focus:
Key points: knowing that exercise can make people's breathing and heartbeat accelerate rapidly, and breathing and heartbeat will gradually return to normal after rest.
Difficulties: Learn to measure your breathing and heartbeat correctly.
Teaching preparation: self-made multi-channel demonstration consultation stethoscope, with stopwatch, straw and self-made breathing counter.
Process design of intransitive verb teaching activities: 1
First, import
1. Dialogue: Do students like sports? Tell me what sports you usually do. So what will happen to our body after exercise compared with before exercise? When the students mentioned the rapid breathing and heartbeat, they asked them: Do you know why our breathing and heartbeat will accelerate after exercise?
(Design intention: By guiding students to recall their physical changes after participating in sports and talking about their feelings after sports, we can get the changes of heart rate and breathing rate before and after sports, which will pave the way for the later teaching, arouse students' attention to the influence of sports on breathing and heart rate, and stimulate students' interest in learning. Ask questions to understand students' preliminary understanding of this problem, and prepare for other teaching activities in this unit)
2. It seems that the changes of people's breathing and heartbeat times before and after exercise are the most obvious. Have you personally measured your breathing and heartbeat before and after exercise? In this lesson, let's measure the number of breaths and heartbeats before and after exercise and find out their relationship with exercise. (blackboard writing topic)
Secondly, measure the breathing and heartbeat times per minute in three states.
1. communication: since it comes to measurement, the accuracy of measurement data is the most important. Can we accurately measure the number of breaths and heartbeats in one minute? Please study together in groups for 3 minutes. Measure it with my own breathing counter.
(student discussion, teacher guidance)
2. Is there any result? Each group first chooses what they want to tell you to report, and the other groups listen to whether there are any different opinions. (Students respond to requests for explanation and demonstration. Emphasis: one breath is one breath-finally, the method of measuring heartbeat is unified: touch the heartbeat or pulse with your hand)
(Design intention: It is very important to guide the measurement method before the actual measurement. Select the appropriate measurement method through discussion and report, put forward the measurement requirements, and list the matters needing attention in measurement. What is breathing? Make clear what heartbeat is and how to measure it correctly. The purpose is to ensure the accuracy of measurement data, which is the fundamental feature of science class)
3. With the method and standard of measurement, we will actually measure it next. First, let's measure the heartbeat. You can use the method that you feel most clearly. How many times does our heart beat a minute? Just like this, in order to make the measurement result more accurate, I used my self-made multi-channel demonstration and consultation stethoscope with stopwatch to measure it. Count the number of heartbeats by yourself. When you hear the stop sound, record your heartbeat on your own record. (measured within 1 min)
(Design intention: The purpose of allowing students to make predictions is to stimulate students' interest and attract students to pay more attention to experimental data. )
Measure your breath in the same way. Remind students not to deliberately change the frequency of breathing.
5. Conversation: Did you record it? Is it the same as the data of heartbeat and breathing times that you began to predict? Please compare your heartbeat and breathing times with others in the group and see what you find.
(Panel discussion-report)
(Design intention: after the measurement, guide students to analyze the data measured by the group, make them realize that there are similarities in the differences, and cultivate students' inductive analysis ability.)
Summary: Everyone's breathing and heartbeat times are different, but generally breathing is about 20 times and heartbeat is about 80 times.
6. Just now we measured the number of heartbeats and breaths in a quiet state. So, after taking part in sports, what will happen to our heartbeat and breathing every minute? In this way, we do exercise first, and then actually measure. Requirements: measure the heart rate first after exercise. (Exercise 1 min, and record the number of heartbeats)
7. Just now, everyone worked hard when doing exercise and measured carefully. Let's watch a beautiful video and have a rest, but there are conditions: after watching the video, continue to measure the heartbeat. (Students watch the video-continue to measure the heartbeat and record it)
8. Just now, we measured the number of heartbeats per minute after exercise and after a short rest, so will our breathing times change after exercise and after a short rest? Let's measure it again in the same way! (Measure and record in the same way as 1 and 2)
(Design intent: This part is to measure the breathing and heartbeat times after exercise and after resting for 3 minutes. Pay attention to collect the breathing and heartbeat times after exercise in time, and record them in time. Play videos during the break to help students adjust their mood and relax, and continue to collect the third set of data to prepare for the later analysis of the data. )
Third, sort out and analyze the data to form an explanation.
1. Just now, we collected the data of heartbeat and breaths per minute in "quiet state", "at the end of exercise" and "after rest". For scientists, it is not enough to just observe the data collected in statistical tables, but also to analyze and sort out these data and find out their changing rules. This requires the help of the more intuitive bar chart or broken line chart we have learned in math class (show the chart and talk about the composition of the chart). Can you choose to use one of these statistical charts to make statistical charts like scientists?
(Design intention: The intervention of statistical chart aims to let students know that making the data in statistical table into a bar or broken line statistical chart can explain the problem more intuitively and vividly, and making statistical chart is also a good way to sort out the data. )
Give everyone 10 minutes. After making the statistical chart, see what you find according to the statistical chart. (Students draw pictures, discuss and communicate in groups)
(Design intention: On the basis of sorting out the data, organize students to analyze the three groups of data collected, so as to explain what they see, that is, guide them to find that breathing and heartbeat times are related to exercise. This is the fundamental purpose of scientific inquiry)
2. Students report. Teachers guide students to report, so that students' findings develop from focusing on objective facts to regular explanations.
Fourth, extension.
Through the study of this lesson, we find that sports will affect our breathing and heartbeat. Do you have any questions to ask after studying here?
"Measuring respiration and heartbeat", the key point is to let students discover the influence of exercise on respiration and heartbeat through the analysis of data, and the difficulty is how to collect more accurate data.
1. Small information:
Reference number of breathing and heartbeat of people of different ages at rest.
Respiratory rate, heartbeat rate
Age, breaths per minute, age, heartbeat per minute.
40-50 times of newborn 140
5-year-old children 20-30 times, 3-year-old children 1 10.
/kloc-children under 0/0 25 times/kloc-children under 0/00.
15 years old adolescents are less than 20 times 10 years old adolescents 90
Adult 16- 18 times that of adult male 70-72.
Adult female 76
2. Understand the causes of rapid heartbeat and breathing after strenuous exercise.
Dialogue: The heartbeat keeps the blood circulating in the human body, and the blood continuously delivers oxygen and nutrients to all parts of the human body, and at the same time discharges the waste gas produced in the body through the lungs. So, what changes have taken place in the blood circulation in the human body due to the accelerated heartbeat? The rapid heartbeat accelerates the blood circulation of the human body. )
Think about it, why does breathing accelerate during exercise?
Explain why breathing and heartbeat accelerate at the same time after strenuous exercise. The human body needs to consume more oxygen and energy during exercise, which requires the lungs to inhale more oxygen and the heart to pump more blood, which leads to the phenomenon that breathing and heartbeat are accelerated at the same time. The human body needs more oxygen during exercise than during rest, so it is necessary to speed up the blood circulation by speeding up the heartbeat and breathing to supplement the large amount of oxygen needed during exercise, so as to ensure the human body to exercise vigorously. )
3. Understand that it is necessary to take part in physical exercise regularly to enhance cardiopulmonary function.
When climbing a tall building, some students will be panting, but some students' breathing will not change much. Discussion: What might cause this difference?
What will happen to people who often take part in physical exercise?
② What about people who don't exercise or exercise less?
The main reason for this difference is that people who exercise regularly have stronger heart beating and stronger lung breathing ability than those who don't exercise regularly. Therefore, when people exercise regularly, their hearts and lungs can provide enough oxygen for the human body, so they are not prone to panting. However, people who don't often take part in physical exercise have a weak heart and a weak ability to supply oxygen to the heart and lungs, which can't meet the needs of the human body for oxygen when engaged in strenuous exercise or heavy work. By accelerating the number of breaths and heartbeats, it is particularly prone to panting.
Who is more generous than the primary school science experiment report?
I. The purpose of the experiment
Controlling factors of water evaporation rate
Two. experimental procedure
1. Question: What factors affect whose evaporation rate?
2. Establish a hypothesis that temperature can affect the rate of water evaporation.
3. Design scheme:
① Experimental materials: alcohol lamp, two glass slides, two tweezers, rubber dropper and beaker filled with water.
② Experimental method: Use a rubber dropper to suck a small amount of water from the beaker, drop 2-3 drops of water on each of the two slides, and clamp them with tweezers; One of the slides was placed on a burning alcohol lamp, and the evaporation rate of the two slides was observed.
③ Precautions: When the glass slide is heated by alcohol lamp, it should be heated by external flame; Preheating before heating; There should be a certain distance between the two slides.
④ Observation result: The water on the glass slide heated by the alarm lamp evaporates faster than that on the glass slide at room temperature.
Three. come to a conclusion
The higher the temperature, the faster the water evaporates.
At the same time, it is also related to the contact area between water and air, as well as the wind speed of the water surface, the speed of stirring the water surface and the air pressure.
Experimental report on how scientific light spreads in primary schools: Use four small A4 papers and three perforated papers, clamp the bottom with a clip, then lay it flat at a certain distance, and then illuminate it with a flashlight. Conclusion: Light travels in a straight line.
How to make use of scientific experiments in primary schools must first have ideas, what kind of experiments you want to do and what kind of effects you want to achieve. After that, prepare experimental equipment, which can be purchased in Taobao, Leke Space and other places. Finally, it is practical implementation and repeated improvement. This year, with the popularity of STEAM education concept in Europe and America, more and more parents and students are interested in scientific experiments.