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Anonymous users2024-02-07Accurate to the last 10 digits? Dude, no kidding, really. If you assume that the full circle is in line with the actual shape, the error is much more than that.
As for the third question, I can tell you that it is ** ball, and the reason is 2:1The mass of the metal is proportional to the cube of the diameter, the cross-sectional area is proportional to the square of the diameter, and the resistance of the sphere is proportional to the cross-sectional area, so the 10cm ball is less affected by the resistance than the 5cm one, and the density of ** is greater than that of aluminum, and the actual impact is even smaller; And the distance of 20m is not enough for these two balls to reach equilibrium speed (reaching it does not affect the result), and if you consider it a little finer, considering the earth's magnetic field, ** balls are also less affected than aluminum balls.
1 and 2 will tell you when I get off work to sort it out.
I forgot to play games at night. It's just cutting the magnetic line, forget it, you don't need to think about this here.
Although the equilibrium speed is generally not reached, it can be used for reference, because the motion process is very simple, that is, a variable acceleration process with smaller acceleration, and the two change laws are the same.
Pure aluminium density:;
**Density: drag formula quote: f=null) SV2 coefficient k and air density (null) taken.
g = ignore form factor.
f=4 3 (ball) r 3g=null) sv 2
v=sqr(8rg (sphere) 3 (empty)k), so it is proportional to the development of density and radius.
v gold = 115m s , v aluminum = , ratio v gold v aluminum = sqr (
As for the first question, the density of the cowhide ball is about 2 3 times that of water. Therefore, 20m fall, ignoring air resistance, the theoretical speed is 20m s; Consider the resistance: the ultimate speed is about 13m s=, as for the average speed, I am too lazy to calculate, if you have studied calculus, it is easy to calculate.
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Anonymous users2024-02-06Hello friends, the change in the motion of the object is essentially affected by the action of the force, and in the case you assume, the physical quantity provided should involve the average force area in the air when falling, and the diameter can also be found. It also involves the value of the local gravitational acceleration, which can generally be taken as g=10 or g=,. If the air resistance is not taken into account, s (distance 20 m) = 1 2 x gt 2
v (landing speed) = gt (free fall, initial velocity is 0) It is worth noting that in the process of falling, the air resistance changes with the change of speed, and the speed changes with the change of time, because it is only 20 meters, so it is recommended to take the air resistance as the average value and set it to f empty.
Therefore, during the falling of an object, the resultant external force experienced by it is f-g-f-empty.
So the acceleration of the fall of the object is a=f and m
In this way, the physical quantities s and v can be calculated (ibid.).
The average speed is half that of V.
The last question: If the air resistance is not considered, then both hit the ground at the same time, because the acceleration is g; If the air resistance is considered, it is necessary to take the resultant external force a=(g-f empty) m of the two to see who is bigger, who is bigger and who lands fast, so as to speculate that the aluminum ball will land first.
You can ask and ask.
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Anonymous users2024-02-05The acceleration g is different at different latitudes and heights, and the standard value is m s 2. From h=1 2 gt 2, the time it takes for the baseball to hit the ground is seconds, and the landing speed is v=gt= m s, so the average velocity is v t=, which is equal to kilometers and hours.
Air resistance only has a noticeable effect on light, large surface areas such as feathers and paper, and is negligible here. The average velocity of a metal ball is also kilometers per hour.
Landing at the same time. The air resistance is negligible, and the inertial mass of the falling object is directly proportional to the gravitational mass, so it always lands at the same time.
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Anonymous users2024-02-04The falling time is only related to the height, so when it lands at the same time, the speed is about the root number (2*20*approx.)
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Anonymous users2024-02-03You take the velocity, and you take the horizontal and vertical accelerations, and you combine the acceleration into the direction of the combined acceleration, which is the direction of the force of the rod on the ball, and then you multiply the mass of the ball by the acceleration and you get the amount of force.
After the strike, the horizontal velocity and the vertical velocity are both 25, and the number 2 is about equal to the change in the vertical direction, and the horizontal velocity is 40+
The action time is So the acceleration vertical is 3768m s horizontally and vertically, and the horizontal force and vertical force are 1768* 3768*, and the resultant force is 624n, and the direction is angular to the horizontal, arctan565, 265, 65°
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