The topic is dedicated to those students who are only in their first year of physics. Here we will talk not only about how distance is indicated in physics, but also about other interesting things. Let this subject be interesting in all sections and topics.
What is the distance?
In physics, each has its own symbol (designation either in Latin or with a Greek letter). All this is done to make it easier and not confusing. Agree, you can get tired of writing something like this in a notebook: distance = speed x time. And in physics there are very, very many different formulas with many parameters. Moreover, there are both square and cubic quantities. So what letter represents distance in physics? Let us immediately make a reservation that there are two types of designation, since distance and length have the same values and the same units of measurement. So, “S” is the same designation. You will come across such a letter in problems or formulas from the “Mechanics” section.
Believe me, there is nothing difficult in solving problems. But provided that you know mathematics and are good at it. You will need knowledge of operations with fractions, the ability to count, open parentheses, and solve equations. Without such skills, physics will be very difficult.
Examples from life
What is distance? We have already understood how distance is designated in physics. Now let's understand the concept.
Imagine that you are now standing near your house. Your task is to get to school. The road is straight all the time. Walk for about two minutes at most. From the entrance door to the school door is 200 meters. This is the distance. What would a description of your walk from home to school look like?
Why didn’t we write “meters”, but limited ourselves to just the letter? Because this is the abbreviated letter designation. A little later we will get acquainted with other parameters that are related to distance.
Now imagine that the path from home to the store is winding. If you look at a map of your area, you will see that the distance to the store from home is the same as to the school. But why is the path so long? Because the road is not straight. You have to cross at a traffic light, go around a huge residential building, and only then do you get to the store. In this case, the actual distance will be much greater. In geometry and physics it means "crooked path." But a straight line is just pure distance, as if you were walking through the wall of a large house. You can also give an example with a man who goes to work.
What does distance have to do with it?
The concept of “distance” cannot exist on its own; it must play some role. For example, you ride your bike to school instead of walking because you are late. As we said earlier, our path to school is direct. You can safely drive on the sidewalk. Naturally, if you travel on foot, it will take longer than to travel by bicycle. What's the matter here? We are, of course, talking about the speed at which you move. Later we will see formulas that will tell us, Physics is a science in which you have to calculate something. Agree, it’s interesting how fast you ride a bicycle? If you know exactly the distance to school and the time of travel, you will find the speed.
So, we now have two more parameters:
v - speed.
Everything will be much more interesting if you learn to work with formulas and find the unknown using fractions. Let us just recall the rule from mathematics: everything that is next to the unknown goes into the denominator (that is, down the fraction). For example, the distance formula (physics) is the product of time and speed. And in other cases - fractions. Look at the picture that shows how to find distance, speed and time. Be sure to practice and understand how such formulas are obtained. Everything follows only from the laws of mathematics; there is nothing fictitious in these formulas. Let's practice (don't peek): what letter represents distance in physics?
What are they measured in?
Let's hope that you remember the designation of the main quantities and their designations. It's time to study units of measurement. Here, too, you will have to train your memory and remember. It is important to know not only how distance is designated in physics, but also time and speed. But this is just a small topic. It will be more difficult later. Let's get started:
S - distance - meter, kilometer [m], [km];
v - speed - meters per second, kilometers per hour [m/s], [km/h] (in this case, kilometers per second can be used;
t - time - second, minute, hour [s], [min], [h].
Pay attention to how speed is indicated. That's right, a fraction. Now imagine this: S/t=m/s or S/t=km/h. This is where fractions come from. In the SI system of international units, these parameters have the following values: meter, second, meter per second.
We figured out how distance is designated in physics, looked at time and speed, which are inextricably linked with it.
The concept of speed is widely used in science: mathematics, physics, mechanics. Schoolchildren begin to get acquainted with it already in the third grade. This happens in more detail in grades 7-8. In the generally accepted sense, speed is a quantity that characterizes how quickly an object moves in space per unit time. Depending on the application, speed is indicated by different symbols.
How is speed indicated in mathematics?
In mathematics textbooks, it is customary to use the lowercase capital letter v. Speed is related to the distance traveled and the time it takes to travel.
With uniform motion, the value v=S/t, where:
- S is the distance traveled by the body,
- t – time of movement.
How is speed indicated in physics?
The branch of physics called mechanics also studies speed. The designation of speed depends on whether it is a vector quantity or a conventional one. In the first case, an arrow pointing to the right → is placed above the letter v. If there is no need to take into account the direction, then the usual symbol v is used.
Speed units
In the international system of units of measurement, it is customary to operate in meters per second (m/s). At the same time, the generally accepted units of measurement are kilometers per hour (km/h), knot (nautical miles per hour).
What is the speed of light and sound?
Scientists have proven that the speed of light is the absolute value at which information and energy can travel. This indicator is constant and equal to 299,792,458 ± 1.2 m/s. The Latin letter s was chosen as its symbol.
The speed of sound depends on the density and elasticity of the medium in which sound waves propagate. It is measured in Machs. For example, supersonic speed ranges from Mach 1.2 to Mach 5. Anything higher is called hypersonic speed.
Obviously, the symbol that denotes speed depends on the mathematical or physical meaning with which this concept is imbued.
How to solve motion problems? Formula for the relationship between speed, time and distance. Problems and solutions.
Formula for the dependence of time, speed and distance for grade 4: how is speed, time, distance indicated?
People, animals or cars can move at a certain speed. In a certain time they can travel a certain distance. For example: today you can walk to your school in half an hour. You walk at a certain speed and cover 1000 meters in 30 minutes. The path that is overcome is denoted in mathematics by the letter S. Speed is indicated by the letter v. And the time it takes to travel is indicated by the letter t.
- Path - S
- Speed - v
- Time - t
If you are late for school, you can cover the same route in 20 minutes by increasing your speed. This means that the same path can be covered in different times and at different speeds.
How does travel time depend on speed?
The higher the speed, the faster the distance will be covered. And the lower the speed, the more time it will take to complete the journey.
How to find time knowing speed and distance?
In order to find the time it took to travel a path, you need to know the distance and speed. If you divide the distance by the speed, you get the time. An example of such a task:
Problem about the Hare. The Hare ran away from the Wolf at a speed of 1 kilometer per minute. He ran 3 kilometers to his hole. How long did it take the Hare to reach the hole?
How can you easily solve motion problems where you need to find distance, time or speed?
- Read the problem carefully and determine what is known from the problem statement.
- Write this information on your draft.
- Also write what is unknown and what needs to be found
- Use the formula for problems about distance, time and speed
- Enter known data into the formula and solve the problem
Solution for the problem about the Hare and the Wolf.
- From the conditions of the problem we determine that we know the speed and distance.
- We also determine from the conditions of the problem that we need to find the time it took for the hare to run to the hole.
We write this data in the draft, for example:
Time - unknown
Now let's write the same thing in mathematical symbols:
S - 3 kilometers
V - 1 km/min
t — ?
We remember and write down in a notebook the formula for finding time:
t=S:v
t = 3: 1 = 3 minutes
How to find speed if time and distance are known?
In order to find the speed, if time and distance are known, you need to divide the distance by time. An example of such a task:
The Hare ran away from the Wolf and ran 3 kilometers to its hole. He covered this distance in 3 minutes. How fast did the Hare run?
Solution to the motion problem:
- We write down in the draft that we know the distance and time.
- From the conditions of the problem we determine that we need to find the speed
- Let us recall the formula for finding speed.
Formulas for solving such problems are shown in the picture below.
Formulas for solving problems about distance, time and speed We substitute the known data and solve the problem:
Distance to the hole - 3 kilometers
The time it took the Hare to reach the hole - 3 minutes
Speed - unknown
Let's write these known data in mathematical symbols
S - 3 kilometers
t - 3 minutes
v — ?
We write down the formula for finding speed
v=S:t
Now let’s write down the solution to the problem in numbers:
v = 3: 3 = 1 km/min
How to find the distance if you know the time and speed?
To find the distance, if the time and speed are known, you need to multiply the time by the speed. An example of such a task:
The Hare ran away from the Wolf at a speed of 1 kilometer in 1 minute. It took him three minutes to reach the hole. How far did the Hare run?
Solution to the problem: We write down in the draft what we know from the problem statement:
The speed of the Hare is 1 kilometer in 1 minute
The time the Hare ran to the hole was 3 minutes.
Distance - unknown
Now, let's write the same thing in mathematical symbols:
v — 1 km/min
t - 3 minutes
S — ?
Let us recall the formula for finding the distance:
S = v ⋅ t
Now let’s write down the solution to the problem in numbers:
S = 3 ⋅ 1 = 3 km
How to learn to solve more complex problems?
To learn how to solve more complex problems, you need to understand how simple ones are solved, remember what signs indicate distance, speed and time. If you can’t remember mathematical formulas, you need to write them down on a piece of paper and always keep them at hand while solving problems. Solve simple problems with your child that you can come up with on the go, for example, while walking.
A child who can solve problems can be proud of himself
When solving problems about speed, time and distance, they often make a mistake because they forgot to convert units of measurement.
IMPORTANT: The units of measurement can be any, but if the same problem has different units of measurement, convert them to the same ones. For example, if the speed is measured in kilometers per minute, then the distance must be presented in kilometers and the time in minutes.
For the curious: The now generally accepted system of measures is called metric, but this was not always the case, and in the old days other units of measurement were used in Rus'.
Problem about a boa constrictor: The baby elephant and the monkey measured the length of the boa constrictor in steps. They moved towards each other. The speed of the monkey was 60 cm in one second, and the speed of the baby elephant was 20 cm in one second. They took 5 seconds to measure. What is the length of a boa constrictor? (solution under the picture)
Solution:
From the conditions of the problem we determine that we know the speed of the monkey and the baby elephant and the time it took them to measure the length of the boa constrictor.
Let's write down this data:
Monkey speed - 60 cm/sec
Baby elephant speed - 20 cm/sec
Time - 5 seconds
Distance unknown
Let's write this data in mathematical symbols:
v1 — 60 cm/sec
v2 — 20 cm/sec
t - 5 seconds
S — ?
Let's write the formula for distance if the speed and time are known:
S = v ⋅ t
Let's calculate how far the monkey has traveled:
S1 = 60 ⋅ 5 = 300 cm
Now let’s calculate how far the baby elephant has walked:
S2 = 20 ⋅ 5 = 100 cm
Let's sum up the distance the monkey walked and the distance the baby elephant walked:
S = S1 + S2 = 300 + 100 = 400 cm
Graph of body speed versus time: photo
The distance covered at different speeds is covered in different times. The higher the speed, the less time it will take to move.
Table 4 class: speed, time, distance
The table below shows data for which you need to come up with problems and then solve them.
| № | Speed (km/h) | Time (hour) | Distance (km) |
| 1 | 5 | 2 | ? |
| 2 | 12 | ? | 12 |
| 3 | 60 | 4 | ? |
| 4 | ? | 3 | 300 |
| 5 | 220 | ? | 440 |
You can use your imagination and come up with problems for the table yourself. Below are our options for the task conditions:
- Mom sent Little Red Riding Hood to her grandmother. The girl was constantly distracted and walked through the forest slowly, at a speed of 5 km/hour. She spent 2 hours on the way. How far did Little Red Riding Hood travel during this time?
- Postman Pechkin was carrying a parcel on a bicycle at a speed of 12 km/h. He knows that the distance between his house and Uncle Fedor's house is 12 km. Help Pechkin calculate how long it will take to travel?
- Ksyusha's dad bought a car and decided to take his family to the sea. The car was traveling at a speed of 60 km/h and the journey took 4 hours. What is the distance between Ksyusha’s house and the sea coast?
- The ducks gathered in a wedge and flew to warmer climes. The birds flapping their wings tirelessly for 3 hours and covered 300 km during this time. What was the speed of the birds?
- The AN-2 plane flies at a speed of 220 km/h. He took off from Moscow and flies to Nizhny Novgorod, the distance between these two cities is 440 km. How long will the plane travel?
Answers to the given problems can be found in the table below:
| № | Speed (km/h) | Time (hour) | Distance (km) |
| 1 | 5 | 2 | 10 |
| 2 | 12 | 1 | 12 |
| 3 | 60 | 4 | 240 |
| 4 | 100 | 3 | 300 |
| 5 | 220 | 2 | 440 |
Examples of solving problems on speed, time, distance for grade 4
If there are several objects of movement in one task, you need to teach the child to consider the movement of these objects separately and only then together. An example of such a task:
Two friends Vadik and Tema decided to take a walk and came out of their houses towards each other. Vadik was riding a bicycle, and Tema was walking. Vadik was driving at a speed of 10 km/h, and Tema was walking at a speed of 5 km/h. An hour later they met. What is the distance between Vadik's and Tema's houses?
This problem can be solved using the formula for the dependence of distance on speed and time.
S = v ⋅ t
The distance that Vadik traveled on a bicycle will be equal to his speed multiplied by the travel time.
S = 10 ⋅ 1 = 10 kilometers
The distance traveled by Theme is calculated similarly:
S = v ⋅ t
We substitute the digital values of its speed and time into the formula
S = 5 ⋅ 1 = 5 kilometers
The distance that Vadik traveled must be added to the distance that Tema traveled.
10 + 5 = 15 kilometers
How to learn to solve complex problems that require logical thinking?
To develop a child’s logical thinking, you need to solve simple and then complex logical problems with him. These tasks may consist of several stages. You can move from one stage to another only if the previous one has been solved. An example of such a task:
Anton was riding a bicycle at a speed of 12 km/h, and Lisa was riding a scooter at a speed 2 times less than Anton's, and Denis was walking at a speed 2 times less than Lisa's. What is Denis's speed?
To solve this problem, you must first find out Lisa’s speed and only then Denis’s speed.
Who goes faster? Friends problem Sometimes textbooks for grade 4 contain difficult problems. An example of such a task:
Two cyclists rode out from different cities towards each other. One of them was in a hurry and rushing at a speed of 12 km/h, and the second was driving slowly at a speed of 8 km/h. The distance between the cities from which the cyclists left is 60 km. How far will each cyclist travel before they meet? (solution under photo)
Solution:
- 12+8 = 20 (km/h) is the total speed of two cyclists, or the speed at which they approached each other
- 60 : 20 = 3 (hours) - this is the time after which the cyclists met
- 3 ⋅ 8 = 24 (km) is the distance traveled by the first cyclist
- 12 ⋅ 3 = 36 (km) is the distance traveled by the second cyclist
- Check: 36+24=60 (km) is the distance traveled by two cyclists.
- Answer: 24 km, 36 km.
Encourage children to solve such problems in the form of a game. They may want to create their own problem about friends, animals or birds.
VIDEO: Movement problems
One day, a random passer-by asked Aesop: “How soon will I get to the city?” Aesop replied: “I don’t know.” The passerby had no choice but to continue on his way - and then Aesop shouted after him: “You will reach the city by noon!” The passerby was surprised: “Why didn’t you answer me right away if you knew the answer?” And Aesop said: “How could I say this without knowing how you walk?”
Indeed, it has long been known that time, distance and speed are interrelated quantities. It logically follows from this that knowing two of them, you can calculate the third. The formula also seems extremely logical: if the speed is, for example, 60 km/h (let’s take the permitted speed of a car in the city as an example) – i.e. in an hour he travels 60 kilometers, then to find the distance he will cover in two hours, we just need to multiply sixty by two - as a result we get 120 kilometers.
Let's put this in the form of a formula. Distance in physics is usually denoted by the Latin letter S - why this is so cannot be said with certainty, it is associated with the German word “Spur”, which translates as “rut” or “trace”, and with the Latin words “sulcus” - which means “furrow” ” – and “semita”, translated as “path” or “path”. The origin of the notation for the other components of this formula is clearer. Time is denoted by the Latin letter t - from the Latin word “tempus”, which, in fact, means “time” (the musical term “tempo” also goes back to it - although some “confusion” can be seen in this: tempo in music is everything - still closer to the concept of speed than time). Time is the Latin letter v, which is again connected with Latin: “speed” in this language is called “velocitas”.
So, the distance formula looks like this: v×t=s
Based on this - and knowing the rules of multiplication and division, of course, which are studied in the second grade, when they begin to solve such problems - we can easily find other components. As we remember from elementary school, in order to calculate one of the factors, it is necessary to divide the product (i.e., the result of multiplication) by the other of them. In other words, we divide the distance (s) by the time (t) - we get the speed (v), but if we need to calculate the time (v) - we do the opposite, i.e. divide the distance by time.
There is nothing complicated in such calculations - so second-graders can easily cope with them... however, such a formula assumes that the object with which we are dealing is constantly moving at the same speed (such movement in physics is called uniform) - that This is not always the case in reality. What to do if the speed of a moving body changes - as happens, for example, when a car starts moving?
Here we are already dealing with a more complex formula - namely, the formula for uniformly accelerated motion, for which we have to introduce a new quantity - acceleration, traditionally denoted by the Latin letter a. To calculate the distance during uniformly accelerated motion (assuming that the body starts from rest), we will have to multiply the acceleration by the squared time, and divide the result by two.
One question remains - how to calculate acceleration? To do this, you need to know the initial speed and the final speed, the relationship between which is characterized by the following formula:
(v is the final speed, and v0 is the initial speed). “Pulling out” acceleration from this formula is not a problem: we subtract the initial speed from the final speed and divide the result by time.
It only remains to add that we owe the formulas characterizing uniformly accelerated motion to G. Galileo, who studied this phenomenon using the example of acceleration during free fall.
Lesson objectives:
- introduce the concept of speed as a new unit of measurement; establish dependencies between quantities - speed, time, distance; learn to solve problems of finding speed from a known distance and time of movement using the formula of movement;
- repeat tabular and extra-tabular cases of multiplication and division, develop computational skills, consolidate knowledge of units of time and length;
- promote the development of logical thinking, attention, speech, independence;
- instill an interest in physical education and sports.
Planned achievements of students in the lesson:
- know the concept of speed as a new unit of measurement, be able to solve problems of finding the speed of movement from a known distance and time of movement;
- consolidate tabular and extra-tabular cases of multiplication and division, knowledge of units of length and time.
Equipment: Peterson L.G. Mathematics, grade 3, part III; math workbook, signal cards, tables with differentiated tasks for independent work, names of units of length and units of time on cards, individual cards for students, drawn characters of “Sesame Street” (Zelibob, Cube, Bead).
DURING THE CLASSES
- Self-determination for activity.
I want to start the lesson with the words of the French philosopher J.J. Rousseau (1712-1778): “You are talented children! Someday you yourself will be pleasantly amazed at how smart you are, how much and how well you can do, if you constantly work on yourself, set new goals and strive to achieve them...” I wish you today in class to be convinced of these words, because what awaits you discovery of new knowledge when solving problems.
- Updating knowledge.
- Having learned that you like to watch children's television programs, I invited the heroes of one television show to our lesson. And they will appear here as soon as you name this program. But the words are encrypted. What to do?
- That's right, you need to solve the examples and decipher the words. To do this, you need to remember tabular and extra-tabular cases of multiplication and division.
- Prepare signal cards and check that the examples are solved correctly.
(Two students work individually on cards.)
Individual tasks on cards
- Why did some guys make mistakes? How to avoid this?
- What do we advise them?
- Read the words, arranging the answers in descending order.
Option I – first word (1 column)
Option II – second word (2nd column)
- Who's ready? (Street, Sesame)
- Well done, your knowledge helped you decipher the names of the program. Our guest is “Sesame Street”.
- Name the heroes of this program. (Zelibob, Bead and Cube)
- Our friends lead a healthy lifestyle, learn to eat right, and play sports. Being keen on skiing, Zeliba and Kubik decided to take up skiing seriously and prepare for the Winter Olympic Games, which will be held in Sochi in 2014.
The bead announced the start. The opponents covered a distance of 24 meters. Zeliboba reached the finish line after 3 minutes, and Kubik after 4 minutes.
Problematic question: Why did it happen? (One moved faster and the other slower)
- Yes, they moved at different speeds.
- Where did you come across the concept of “speed”? (In a car, the speedometer measures speed)
- How to measure the speed of moving bodies that do not have a speedometer?
- Name the topic of the lesson.
- What will we learn to measure in class?
- Setting the lesson topic
- To more accurately formulate the topic and goals of the lesson, we will find supporting words. They are necessary to determine speed. To do this, working in pairs, arrange the units of measurement given to you in ascending order.
- What are the units of measurement for rows I and III? (Lengths)
- In row II? (Time)
Who is ready to name them in ascending order? (Students name and lay out on the typesetting canvas.)
mm, cm, dm, m, km
s, min, h, day, month
Check your execution, turn over each card and read the word. (I and III rows: distance; II row: time)
Distance- this is the gap between two points, points, between something. How is distance measured? (In units of length).
Time- this is the duration, the duration of something. How is time measured? (In units of time).
Problematic question:
- What is called speed?
- How is speed measured?
- Check the topic of our lesson. (Speed. Time. Distance.)
- What will we learn in class? (Children's answers).
Today we have to learn how the speed of movement is related to the time of movement and distance, learn to solve problems to find the speed of movement.
- Discovery of new knowledge.
- What is speed? Where can we find the answer to our question? (In the textbook)
- Open the textbook with. 1, Find the highlighted word “speed”. Let's read the definition of speed. (Speed is the distance traveled per unit time.)
- So what is called speed?
- What quantities will we use to determine speed? (by distance and time)
- And as units of speed we will use both units of length and units of time.
- Usually they use speed units such as meters per second, meters per minute, kilometers per hour, and write them like this: m/s, m/min, km/h. Please note that the preposition “in” in mathematics was replaced with a dash “/”.
- Read speed units km/s m/min km/h m/s
- What units of measurement are used to form the names of speed units? (From units of length and units of time).
Physical exercise.
We put our hands all together,
A plane appeared.
Flapping the wing back and forth,
Do it once and do it twice.
Release your hands down
And everyone sit down.
Working with the textbook
- I wonder what the speed of the plane is?
- Explain the meaning of the sentences written in task No. 1, p.2. (The plane flies at a speed of 800 km/h, i.e. in 1 hour the plane covers a distance of 800 km)
Well done. Open your notebooks, write down the number, great job. Watch your posture. We will learn to solve problems to find the speed of movement over a given distance and time. Zeliba and Kubik really want to know their speed. Let's help them. Let's solve the problem.
Task 1. Zeliba skied a distance of 24 meters in 3 minutes. How fast was he going?
What do we know?
- Distance – 24 m
- Time – 3 min.
What do you need to know? Zeliba's speed, i.e. distance covered by Zeliboba in 1 minute.
Let's make a drawing for the task
We draw a segment. What is the distance? Let us denote the time on the segment. We can divide the entire path that Zeliboba traveled into 3 equal parts, because at every minute Zeliboba covered the same distance.
- How many of you guessed how fast Zeliba was moving?
- How to find out the speed of its movement?
Notebook entry: 24 ׃ 3 = 8 (m/min) speed of Zeliba.
Those. in 1 minute Zeliba walked 8 m.
Let's write the answer to the problem. Answer: 8 m/min.
- Primary consolidation.
Let’s consolidate the ability to solve problems involving movement, namely finding speed.
Task 2. The cube skied a distance of 24 m in 4 minutes. How fast was the cube moving?
- What is known about the problem? (Distance – 24 m, time – 4 minutes)
- What do you need to know? (Cube Speed)
There is a drawing on the board.
Guys, is it always convenient to make a drawing for a task? In mathematics, it is customary to denote quantities in Latin letters:
- distance – S
- time – t
- speed - v
So, let's write it down in your notebook:
| S | t | v |
| 24 m | 4 min | ? |
- How to find the speed of movement? (Distance divided by time)
- Tell me the same thing, only using lettering: v = S ׃ t
You named the formula by which the speed of movement is found. You will use this formula in high school as well. Let's write down the solution to the problem. (Student at the blackboard).
v = S ׃ t
24 ׃ 4 = 6 (m/min) speed of the Cube.
Answer: 6 m/min.
Compare the speed of Zeliboba and Kubik. Why did Zeliboba reach the finish line earlier?
Conclusion: Speed is a quantity that can be measured and compared.
Zeliba and Kubik are happy. Together with you, they learned to measure the speed of movement.
- Independent work.
Let's practice solving speed problems by doing the work ourselves.
The bead asks you to find the speed of your friends in other sports. Complete the tables, recording only the answers. (Tasks differentiated by complexity and volume.)
How will you find the speed of movement? Be careful when indicating speed.
1 group
2nd group
Check your answers with Businka's answers. Annex 1
- Who completed the work without errors? - Well done, give yourself a 5.
- Who made 1 mistake? – Give yourself a 4. – Bead is happy with you.
- Who made 2 mistakes? Who didn't make it? – Don’t be upset, practice at home, put in the effort, and then you will succeed.
And our friends advise you to go in for sports. Tell me, why do you need to play sports? (Children's answer). That's right, sport is health, strength, endurance.
- Repetition with the inclusion of new knowledge.
Zeliboba has prepared a game for you. We need 3 students - these are moving models: an airplane, a car, a rocket. Another 3 students are driving speeds: 800 km/h; 90 km/h; 6 km/s. Find a pair, match which one of you has what speed?
(Airplane - 800 km/h; rocket - 6 km/s; car - 90 km/h).
- Which one is moving the fastest?
- Who has the slowest speed?
- What type of transport will our friends use to spend less time traveling to Moscow?
You will learn how to find the time of movement in the next lesson.
- Lesson summary. Reflection of activity.
Our lesson is coming to an end. What did you learn in the lesson?
- What is the formula that we will use to determine the speed of movement?
- Where can you apply your new knowledge?
Sesame Street is running out of time. Let's light up the lights on Sesame Street.
- Those who are satisfied with their work in the lesson have understood the new topic - “light up” the red flashlight.
- Those who are not completely happy and have made mistakes are yellow.
- Those who are not happy with their work will “light up” blue.
Your flashlights tell me that you have achieved success in your lesson today.
I wonder how our friends will appreciate your work? (On “Sesame Street” the red flashlight “lights up.”) As you can see, our friends from the Sesame Street program are pleased with your work in the lesson.
- Homework.
The homework will be as follows: solve problems, determine the speed of moving bodies - No. 2, p. 2, or come up with your own problem in which you need to find the speed from a known distance and time, and solve it - No. 8, p. 3.
Thanks for the lesson.