![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
The derivation of the relationship between velocity and displacement in free fall motion
Free fall all formulas
2) Free fall motion 1. Initial velocity VO = 0 2. Final velocity VT = GT 3. Falling height h = GT2 / 2 (calculated downward from VO position) 4. Inference vt2 = 2GH note: (1) free fall motion is a uniformly accelerated linear motion with zero initial velocity and follows the law of uniformly variable speed linear motion; (2)...
Research on free fall movement in physics compulsory one of senior high school 1. Two objects fall freely from a balloon at a certain height. After the first object falls for 1s, the second object begins to fall. The two objects are connected together with a 93.1m long soft rope. Ask: (1) how long has the rope been straightened when the second object falls? (2) What is the velocity difference between two objects at the moment of straightening?
1）v1-v2=10m/s
t=93.1/10=9.13s
2) 10m / S (the speed difference remains unchanged, as can be seen from the image)
All calculation formulas of physics compulsory one in Senior High School
Physical theorem, law, formula table 1. Motion of particles (1) ---- linear motion 1) uniform variable speed linear motion 1. Average speed vping = s / T (definition formula) 2. Useful inference vt2-vo2 = 2As 3. Intermediate time speed VT / 2 = vpping = (VT + VO) / 2 4. Final speed VT = VO + at 5. Intermediate position speed vs / 2 =
High school physics compulsory formula and formula derivation (the derivation process should also be urgent!
Here, let the initial velocity be V0, the acceleration be a, and the time be t. first, v = V0 + at, where at is the velocity change, and then the initial velocity is the current velocity. Then, the total displacement S = v0t + 0.5at ^ 2. This formula has two ideas to prove: 1. Because it is a uniformly accelerated motion, the velocity at the middle time, that is, the average velocity, is the initial
The useful inference vt2-vo2 = 2As is derived from the formula? Is the formula vs / 22 = (VO2 + vt2) / 2 also derived?
1. Average velocity vping = s / T (definition formula) 2. Useful inference vt2-vo2 = 2As
3. Intermediate speed VT / 2 = vping = (VT + VO) / 2 4. Final speed VT = VO + at
5. Intermediate position speed vs / 2 = [(VO2 + vt2) / 2] 1 / 2 6. Displacement S = vping t = VOT + at2 / 2 = VT / 2T
7. Acceleration a = (VT VO) / T {taking VO as the positive direction, a and VO are in the same direction (acceleration) a > 0; Reverse then a
RELATED INFORMATIONS
- 1. How to use the formula of uniform variable speed linear motion in senior high school physics compulsory 1 Is under what circumstances this formula is used
- 2. The time taken for an object to fall freely after the last 200 meters is 4 seconds, then what is the falling time and total height of the object
- 3. Particle is an idealized model. In the following examples, what can treat the research object as a particle is () A. Study the motion law of the earth around the sun B. Study the law of the alternation of day and night on the earth C. Study the time required for the train to run from Fuzhou to Shanghai D. Study the time required for a train to pass the Nanjing Yangtze River Bridge
- 4. A car traveling along a straight highway with uniform acceleration, passing two electric poles 50m apart by the roadside, shares 5S. When it passes the second electric pole, its speed is 15m / s, and when it passes the first electric pole, its speed is () A. 2m/s B. 10m/s C. 2.5m/s D. 5m/s
- 5. A physics problem about uniform variable speed linear motion in high school (about the proportional relationship in special laws) A train starts to move at a constant speed in a straight line from a standstill. One person stands in front of the first carriage to observe. The time for the first carriage to pass through him is 4 seconds, and the time for all trains to pass through him is 12 seconds. The distance between carriages is not recorded, and the length of each carriage is equal. It is required to (1) how many carriages in total; (2) How many cars passed this person in the last 4 seconds; How many seconds did the last three sections pass through this person? I hope it's best to use the proportional relationship in the special law, and attach the description and analysis, not just the formula and answer If the three questions are difficult to answer, you can answer the first one first
- 6. The object changes speed under the action of external force When an object changes speed under the action of external force, the kinetic energy must change The kinetic energy of an object remains unchanged, and the combined external force must be zero Why are these two sentences wrong?
- 7. The artificial satellite makes a uniform circular motion around the earth, its orbit radius is r, its linear velocity is V, and its period is t. if you want to change the period to 2T, what methods can be adopted: A. R remains unchanged, so that the linear velocity becomes 1 / 2V, B.V remains unchanged, and the orbit radius becomes 2R C. yes, the orbit radius becomes (3 times better, 4 times lower) d. increase the height of the satellite by R
- 8. On December 26, 2004, a century tsunami occurred, but animals did not die on a large scale. From a physical point of view: () A some animals can hear ultrasonic waves B some animals can hear infrasound waves
- 9. Hawking introduction
- 10. What is the reason why China's legitimate seat in the United Nations has been restored and China US relations have begun to normalize? A successful development of atomic bomb B improvement of China's comprehensive national strength
- 11. Make up unit Zhang Wei's height is 16.6_____ 7.5km=______ m； 5.85mm=_____ m； 0.068m=_______ nm； 16.4m=______ um； 1.8h=____ min； 45min=_____ h
- 12. As shown in the figure, the parallel metal plates a and B placed along the horizontal direction are respectively connected with the positive and negative poles of the power supply. There is a small hole in the center of the two plates along the vertical direction. Now there is a positively charged droplet. The point P directly above the small hole falls freely from rest, and the speed after successively passing through the two small holes is V1. If the plate a does not move, if the key K is kept open or closed, B When the plate is translated upward or downward for a short distance, the same droplet still falls freely from rest at point P, and the velocity after passing through two small holes successively is v2. The following statement is correct without air resistance () A. If key K remains closed and plate B moves downward, V2 > v1 B. If key K is closed for a period of time and then disconnected, and plate B is moved downward, V2 > v1 C. If key K remains closed, V2 = V1 regardless of moving board B up or down D. If key K is closed for a period of time and then disconnected, no matter moving board B upward or downward, V2 < v1
- 13. As shown in the figure, use the spring scale to horizontally pull the object block weighing 10N, place the object block on the horizontal desktop, and gradually increase the tension. When the indication of the spring scale is 2.2n, the object block begins to slide. In order to maintain the uniform movement of the object block, the later tension is only 2.0N. Then the maximum static friction between the object block and the desktop is______ N. The dynamic friction coefficient between the block and the table is __
- 14. The distance between the slide and the lens position changes between 15 ~ 30cm. In order to get an enlarged image on the screen, which of the following focal lengths should be selected () A. focal length 15cm B. focal length 30cm the correct answer to this question is a, but to get an enlarged image, the object distance should be between F < U < 2F. The farther the lens is, the larger the image will be. Why not choose B and a? Be clear,
- 15. When stone a falls freely from the top of the tower from static S1, stone B falls freely from static S2 from the top of the tower. If the two stones fall to the ground at the same time, the tower height is: () a S1 + S2 B (S1 + S2) ²/ 4S1 C S1 ²/ 4（S1+S2) D (S1+S2) ²/ S1-S2
- 16. As shown in Figure 1, the current in a long straight wire changes according to the sinusoidal law as shown in Figure 2. It is specified that the current is positive from left to right. There is an open metal frame below the straight wire. Therefore, compared with point B, the moment when the potential at point a is the highest is () A. T1 time B. T2 time C. T3 time D. T4 time
- 17. An object with a mass of M = 2kg is stationary on the horizontal plane, and the sliding friction force between the object and the horizontal plane is equal to 0.25 times of the elastic force between them. Now, apply an oblique upward pull force with a size of F = 8N and an angle of 37 degrees with the horizontal direction to the object. It is known that sin37 = 0.6, cos37 = 0.8, g = 10, and calculate the displacement through the object in 5 seconds under the action of the pull force
- 18. If a car flies on rainy days at a speed of more than 150 kilometers per hour, will part of the rain rub shoulders with the body because of the strong airflow formed by too fast speed? (provided that there is no rain from the start to the acceleration above 150, and the rain is not very heavy, between heavy rain and light rain) I just want to know whether an object will form a strong airflow around the body because of its too fast speed, and whether this strong airflow will change the orbit of the object to be contacted?
- 19. Moving car and laser beam That's it. I can't understand this question. I want to know how the laser beam moves? Is it a line or a face? Why are there two situations in the car? Where is the entry point?
- 20. As shown in the figure, when a charged body is contacted with a positively charged electroscope, if (1) The opening angle of the metal foil becomes larger, indicating that the charged body carries () charge (2) The opening angle of the metal foil decreases to 0 °, indicating that the charged body carries () charge (3) After the metal foil is closed and opened, it indicates that the charged body carries () charge, and the amount of charge is greater than that of the electroscope ()