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After a polygon cuts an angle from a vertex, the sum of the inner angles of the new polygon is 2520 degrees
When only one corner is intercepted:
If you pass another vertex, you have one more edge than the new polygon
For example, 17 sides should be calculated upstairs, (17-2) * 180 = 2700 degrees
If there is only one other vertex, it is the same as the number of new polygon edges
The sum of internal angles is also 2520 degrees
RELATED INFORMATIONS
- 1. As shown in the figure, when the board with length of L = 2M and mass of M = 8kg is placed on the horizontal ground, and the speed of the board moving to the right is v = 6m / s, a small block with mass of M = 2kg regardless of size is gently placed at the front end of the board. The dynamic friction coefficient between the board and the ground and between the block and the board is μ = 0.2, g = 10m / S2 (1) The acceleration of the block and the board; (2) the speed of the block sliding away from the board
- 2. Zhang Jun students in "explore the size of friction more which factors." In the experiment of "exploring which factors are related to the size of friction force", Zhang Jun adopted the following experimental methods: put the long board on the horizontal table, and the wood (2) does the long board have to move in a uniform and straight line in the experiment I'm sorry I can't upload the picture, but please make sure to analyze it for me
- 3. Find a board about 1m long, put the board on the horizontal desktop, and pad a few round pencils under it, so that the friction between the board and the desktop is as small as possible What will happen if you find a toy car with batteries and drive it on the board?
- 4. As shown in the figure, in the experiment of studying friction, a small wooden block placed on the horizontal table is pulled horizontally with a spring scale each time, and the reading of the small wooden block's movement is shown in the following table (the contact surface between the wooden block and the table is the same each time): then from the table, we can see () & nbsp; the number of experiments, the movement state of the small wooden block, and the reading of the spring scale (n) 1 static 0.4 2 static 0.6 3 Acceleration 0.7 4 constant speed 0.5 5 deceleration 0.3 A. The maximum friction force on the block is 0.7nb. The maximum static friction force on the block may be 0.5nc. In the five experiments, the friction force on the block is the same three times. D. in the five experiments, the friction force on the block is the same two times
- 5. When exploring the relationship between acceleration, force and mass, why should we balance the friction, and why can we balance the friction by raising one end of the board
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- 16. 73,
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