...离与物理距离的表格形式 6. 摘要 什么是遗传距离(genetic distance)? Genetic distance is the measure of the genetic divergence between species or populati***. This distance is measured using ancestral relati***hips and evolutionary patterns. The similarity between genes is importan...
... 战争装备4 盗贼之海 地平线广场3 伸缩板 衰变状态2 光环战争2 记录 ...
...g downwards, and so there will be an upward resistive force on the paper. 如何计算物体在空中缓慢下落时的空气阻力 For objects which move slowly relative to the air (such as falling dust particles), the resistive force is directly proportional to the object’s velocity relative...
...a vector quantity. The magnitude (size) of this vector quantity gives the distance. If the displacement vector , then the magnitude is given by . In the earlier example, we had a displacement vector of . The magnitude of this vector is .
...用它们来解决沿直线运动的物体的简单运动问题。 距离(distance)和取代(displacement)的区别 Distance is the total length of the path traveled by an object. This is a scalar quantity. Displacement () is the shortest distance between the object’s starting point and the fina...
在学习如何计算向心力之前,让我们先看看什么是向心力,它是如何导出的。在圆形路径中移动的物体即使保持恒定速度也在加速。这种物体所经历的加速度称为向心加速度,它总是指向圆轨迹的中心。根据牛顿第二定...
在本文中,我们将研究如何计算动能。动能是物体运动所产生的能量,它取决于物体的速度和质量。物体的运动方向对动能没有影响。对于一个运动的物体,动能被定义为使物体从静止加速到它的速度所需要做的净功。...
...inertia)? 物体的转动惯量由以下积分定义: where is the distance of the mass element from the axis of rotation. 从物理上讲,转动惯量使物体在受到力矩作用时具有抵抗角加速度的能力(类似于质量抵抗线加速度的能力)。如果转动惯量...
...一海里(a nautical mile)? A Nautical mile is a unit used to measure distances at the sea. Although the unit is not an official SI unit, it is still widely used by sea and air navigators. Traditionally, the nautical mile had been defined as the length of a minute of arc of a longitude (a line ru...
...图显示了单摆: A simple pendulum We take the length to be the distance from the axis of suspension to the centre of gravity of the body (the body in motion in a simple pendulum is often called the “bob”). Then, if we let the bob to oscillate back-and-forth with a **all angle , the...