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Time Line为什么距离是速度时间曲线下方的面积的笔记

微分无限的思想

by 子水 0 0
质量和重力的区分的笔记

Mass is how much stuff there is of something, how does something response to a specific force with Newton's second law.Weight is the force of gravity on a mass or on an object.The force of gravity between two objects is going to be a G which is F=G(m1*m2/r^2).F equals G(m1/r^2) which the "m1" is the mass of the earth, the "r" is the distance from the center to surface that we can get the g=9.8m/s^22. So the gravitional field of earth is 9.8 m/s^2.So the weight is the gravitional field of earth times the mass.The unit of mass is "kg", the unit of weight is the unit of gravitional field which is "m/s^2" times "kg".Then final unit of weight is kg*m/s^2 which is the unit of Newtons, force.If we take the new weight on the Moon which we can get the different gravitional field of Moon than on Earth. But we can still multiply the mass with the gravitional field of moon.Earth is not a perfect "ball", there is different weight in different places in the Earth.England and the United States have different units in weight and mass. The mass is "slug", and the weight is "pound".

by 淡唁 0 0
重力介绍的笔记

You can change everything with as same as gravity, like temperature, or everything theory much like gravity.Gravity is immaterials.The row and the column.By the mass?Force=G*(m1*m2/r2).G=Newtons*(m/kg)^2;"g" as the gravitational field at the surface of Earth which is 9.8 m/s^2;Double force, the third law of the Newtons.

by 淡唁 0 0
恒加速下的平均速度的笔记

"Positive sign" is to right, the "Negative sign" is to left. Same as up and down.How far is gone when it is acceleration, multiply the acceleration and changing time.Final velocity is the intial velocity plus the areas that go when it's acceleration, which is multiply the acceleration and changing time.V(intial)+(t)a=V(final);When at begining the speed is constant velocity, then suddenly change into acceleration which the speed is changing over time.The final the displacement is the constant velocity times changing time add the sum of final velocity-initial velocity over 2 then times changing time.The graph can help solve the problem how far is object gone.Average acceleration is 1/2 times the sum of initial velocity plus final velocity.The displacement when the speed is acceleration, is the changing time times the average velocity.

by 淡唁 0 0
Time Line为什么距离是速度时间曲线下方的面积的笔记

Velocity is equal to displacement over time.Displacement is velocity times time. That's distance.When we have the constant accelerati on.Intial spped is 0.Acceleration is changing velocity over changing time.Changing time is 5 seconds.That graph is a triangle, we know the areas formula for triangle, that areas is the displacement (distance).

by 淡唁 0 0
Airbus A380起飞距离的计算的笔记

If we assume that the acceleration is constant, then we can get the average velocity, will be average of final velocity and initial velocity.Va=Final v elocity+beginning velocity/2.

by 淡唁 0 0
牛顿第一定律的笔记

Every body presists in its state of being at rest of moving uniformly straight forward (constant velocity), except insofar as it is compelled to change its state by force impressed，the law of inertia.Unbalanced force, the two pair of balanced force can cancel each other.Non-friction.Friction come with atomic level, the actual water molecules and elastic structure and the ice cube here and the elastic structure on the ice. Beside, there are air particles.Those situation without the gravity.

by 淡唁 0 0
加速度的笔记

Acceleration is change in velocity over time.A car can go 0-60 mph in 3 seconds.Acceleration is a "a" with arrow which it's 0 mph at begining and 60 mph at the end.So it is 60-0/3=20 miles/hour/second (miles/hour*seconds).The final answer is 20/3600 miles second^2 that equals 1/180 mile/second.

by 淡唁 0 0
求解时间的笔记

Magnitude.The " maybe means to the east in one dimensional, and the "minus" maybe means to the west.

by 淡唁 0 0
计算平均速度速率的笔记

Velocity is a vector quantity.Average velocity is a triangle toward down, displacement is "s", time is "t".Average velocity is displacement divided the time.Add the "little triangle" toward up is "change in".Dimensional analysis which is change units.

by 淡唁 0 0
矢量和标量的介绍的笔记

Vectors which magitude/size and directions.Scalers which only have the magitude/size.Distance is the scalar quantity which have the distance without direction.When talk about the movement, the change in position, and give its direction called displacement.Time only has one direction.Speed is only a scaler quantity which it doesn't have direction.Speed with direction is a vector quantity which it called velocity.If you are thinking about change in position and the direction that it is displacement, without the direction is distance.

by 淡唁 0 0
重力介绍的笔记

万有引力F=GMm/r^2r 两物体的质点距G=6.67*10的负十一次方

by 谛听 0 0
向心力和向心加速度直观解释的笔记

centripetal force 向心力centrifugal force 离心力

by 甘瓜六味 0 0
磁学12的笔记

本节讲解了电磁感应的微观解释切割磁感线，U=Blv

by 甘瓜六味 0 0
磁学10的笔记

=发电机-2=当线圈与磁场垂直，便无法继续旋转。

by 甘瓜六味 0 0
磁学6的笔记

=电生磁=右手定则导线产生的磁场的公式：μI/2πr

by 甘瓜六味 0 0
磁学5的笔记

安培力：F=BIL 推倒过程：F=Bqv=Bq(l/t)=B(q/t)l=BIl

by 甘瓜六味 0 0
磁学4的笔记

r=mv/Bq 应用：偏转带电粒子(curves the path)cathode ray TVscyclotron

by 甘瓜六味 0 0
磁学3的笔记

电子和质子带电量相同，只是质子比电子重。洛伦兹力的方向：左手定则

by 甘瓜六味 0 0
磁学2的笔记

洛伦兹力:F=Bqvsinα B 电场强度的大小：特斯拉 T“电磁学好BT啦TAT”

by 甘瓜六味 0 0

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Time Line为什么距离是速度时间曲线下方的面积的笔记
微分无限的思想
质量和重力的区分的笔记
Mass is how much stuff there is of something, how does something response to a specific force with Newton's second law.Weight is the force of gravity on a mass or on an object.The force of gravity between two objects is going to be a G which is F=G(m1*m2/r^2).F equals G(m1/r^2) which the "m1" is the mass of the earth, the "r" is the distance from the center to surface that we can get the g=9.8m/s^22. So the gravitional field of earth is 9.8 m/s^2.So the weight is the gravitional field of earth times the mass.The unit of mass is "kg", the unit of weight is the unit of gravitional field which is "m/s^2" times "kg".Then final unit of weight is kg*m/s^2 which is the unit of Newtons, force.If we take the new weight on the Moon which we can get the different gravitional field of Moon than on Earth. But we can still multiply the mass with the gravitional field of moon.Earth is not a perfect "ball", there is different weight in different places in the Earth.England and the United States have different units in weight and mass. The mass is "slug", and the weight is "pound".
重力介绍的笔记
You can change everything with as same as gravity, like temperature, or everything theory much like gravity.Gravity is immaterials.The row and the column.By the mass?Force=G*(m1*m2/r2).G=Newtons*(m/kg)^2;"g" as the gravitational field at the surface of Earth which is 9.8 m/s^2;Double force, the third law of the Newtons.
恒加速下的平均速度的笔记
"Positive sign" is to right, the "Negative sign" is to left. Same as up and down.How far is gone when it is acceleration, multiply the acceleration and changing time.Final velocity is the intial velocity plus the areas that go when it's acceleration, which is multiply the acceleration and changing time.V(intial)+(t)a=V(final);When at begining the speed is constant velocity, then suddenly change into acceleration which the speed is changing over time.The final the displacement is the constant velocity times changing time add the sum of final velocity-initial velocity over 2 then times changing time.The graph can help solve the problem how far is object gone.Average acceleration is 1/2 times the sum of initial velocity plus final velocity.The displacement when the speed is acceleration, is the changing time times the average velocity.