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The sum of the two acute angles of a right triangle is greater than the sum of the two acute angles of an obtuse triangle. Right
The sum of the two acute angles of a right triangle is 90 ° obtuse angle. The sum of the two acute angles of a triangle is 180 ° minus this obtuse angle, so it is an acute angle
The sum of the two acute angles of a right triangle must be () degrees; The sum of the two acute angles of an obtuse triangle must be () degrees In an acute triangle, the sum of any two internal angles is () degrees
The sum of the two acute angles of a right triangle must be 90 degrees
The sum of the two acute angles of an obtuse triangle must be 90 degrees
Why can't the inner and outer rails be under pressure at the same time when the turning speed of the train is too small or too large? What else?
The train turning will produce centrifugal force and centripetal force due to inertia, and this factor is taken into account in the design of the rail, so the rail will have a certain deflection angle in the turning section. The outer rail is a little higher than the inner rail. Different speeds of the train will produce different sizes of centrifugal force when turning. Only when the train speed and the design speed
If the radius of a sector is twice the radius of a circle and their areas are equal, the center angle of the sector is?
ninety
How easy is it to add 8 and 5 / 6 plus 9 and 1 / 4 minus 3 and 5 / 6
8 and 5 / 6 plus 9 and 1 / 4 minus 3 and 5 / 6
=8 and 5 / 6 minus 3 and 5 / 6 plus 9 and 1 / 4
=5 plus 9 and 1 / 4
=14 and 1 / 4
(six and three eighths + one and one eighth) × 4.8 what's 13 and 6 / 7
(six and three eighths + one and one eighth) × 4.8 minus 13 and 6 / 7
=7 and 1 / 2 × 4 and 4 / 5-13 and 6 / 7
=36-13 6 / 7
=22 and 1 / 7
RELATED INFORMATIONS
- 1. 7 / 8 minus 6 / 7 =? 2 / 5 + 1 / 6 + 3 / 5 =? Miscellaneous Poems Written by Gong Zizhen
- 2. Physical friction coefficient On the plane, equal volume objects a, B and a are stacked on B. the weight of both objects is 10N, and the friction coefficient between each contact surface is equal to 0.3. At the same time, two horizontal forces with F = 1n act on a and B respectively. FA is horizontal to the right and FB is horizontal to the left. If both objects are stationary, the friction force between B and B on a is: A: 6N 3N B：1N 1N C:0N 1N D:0N 2N
- 3. What is the rolling friction coefficient of the aircraft on the ground
- 4. On a straight road, athletes speed up on their bicycles. What is the direction of friction on the wheels The friction force on the front wheel is backward, and the friction force on the rear wheel is forward. Why,
- 5. Friction direction of bicycle wheel Front and rear wheels. Explain why
- 6. How to describe the change of velocity direction with acceleration in uniform circular motion? In linear motion, it can be said that the speed increases or decreases by X meters per second, but what should be said when it is used to describe the change of speed direction? For example, how does acceleration describe the change of velocity direction in uniform circumferential velocity? Say the speed direction changes x degrees per second?
- 7. As shown in the figure, a small ball with a mass of M is hung with a thin rope with a length of L and placed on a smooth spherical surface with a radius of R. the minimum distance from the suspension point to the spherical surface is D, then how much pressure does the small ball have on the spherical surface? What is the tension of the rope?
- 8. A small object with a mass of 0.05 kg is placed on a smooth horizontal table. One end of a rope is connected to the object, and the other end passes through the small hole in the center of the table. The object originally rotates on the circumference 0.2 m away from the hole at an angular speed of 3 rad / s. now pull the rope down slowly from the small hole to reduce the rotation radius of the object to 0.1 M. then the angular speed of the object
- 9. 7. The object with mass m is pulled by a string through a smooth small hole, and makes a uniform circular motion on a smooth horizontal plane. When the tension is a certain value f, it rotates When the tensile force is a certain value f, the rotation radius is R. when the tensile force gradually increases to 6F, the object still moves in a uniform circular motion. At this time, the radius is R / 2, then the work done by the tensile force on the object is: () A、0 B、FR C、3FR D、5FR/2
- 10. It is known that the circumference of an isosceles triangle is 30 cm and the length of one side is twice the length of the other. Find the length of its three sides
- 11. In a triangle, there are at most acute angles, right angles, obtuse angles and at least acute angles
- 12. I know that the conversion formula between friction coefficient and surface roughness is directly proportional. I want to know that there is a conversion formula. I know the friction coefficient and want to know what the fine roughness is
- 13. What effect does the friction coefficient have on belt drive
- 14. What is the relationship between centrifugal force and centripetal force? What's the difference?
- 15. Several mathematical problems 1. Grandpa played chess with his grandson. Grandpa won one game and scored one point. Grandson won one game and scored three points. He played eight games and recognized that the scores were equal. How many games did they play? Solving the first order equation with one variable 2. The tombstone of the Greek mathematician diophantu records: "one sixth of his life is childhood; another one twelfth of his life is one seventh of his life. He has been married for five years and gave birth to a son. His son lives half of his life. When he dies, he spends another four years (1) What is the age of his marriage? Solve it with a one-dimensional equation (2) What's the age of his death? Solve it with a univariate equation 3. A document needs to be printed, Xiaoming needs 6 hours and Xiaohong needs 8 hours. How long does it take them to complete their work? Solve it with a one-dimensional equation 4. A harvester harvests a wheat field, 25% in the morning and 6 hectares in the afternoon. How many hectares are there in total? Solve it with one yuan one-time equation 5. The store sells two clothes, each of which is 60 yuan. One earns 25% and the other loses 25%. Is it a profit, a loss, or no loss?
- 16. Build a highway, 30% of the total length of the first phase... Urgent! A math problem Build a highway, 30% of the total length of the first phase and 40% of the total length of the second phase. A total of 280 kilometers are built in the two phases. How many kilometers is the total length of the highway? (tell me the formula without calculation. It's best to talk about it.) OK, add
- 17. Both Party A and Party B start from place a at the same time and follow the same route to place B. If Party A walks at the speed of a km / h for half of the time and B km / h for the other half of the time; Half of the distance of B travels at the speed of a km / h, and the other half travels at the speed of B km / h (a, B are greater than 0 and a ≠ b), then () A. A arrives at B first B. B arrives at B first C. Party A and Party B arrive at place B at the same time D. Uncertain
- 18. For a train moving in a straight line with uniform speed change, the speed increases from 10m / s to 15m / s within 50s. What is the acceleration of the train?
- 19. The train advances at the speed of 20m / s. when passing station a, it needs to stop for 120s. The acceleration when entering the station is -0.5m/s2, and the acceleration when leaving the station is 0.4m/s2. After leaving the station, it still needs to move forward at the speed of 20m / s. how much longer does the whole train run because the train stops at station a?
- 20. Brake the train before entering the station. It is known that the train speed before braking is 60km / h and the braking acceleration is 0.8m/s2. Calculate the train speed 15s and 30s after braking