What is the direction of motion of velocity and displacement

The direction of velocity is the instantaneous direction of motion of the particle, and the displacement is generally a process, that is, a directed line from the starting point to the end point, so the direction of velocity is not directly related to the direction of displacement.

The direction of displacement is the difference between the final position and the starting position.

The intermediate state is not taken into account.

Velocity is a direction and a variable is a process quantity.

It can only be said that the direction of velocity affects the direction of displacement but cannot determine.

The direction of the velocity, which is not affected by the direction of the displacement.

In judging the direction is, you have to pay attention to who you are talking about the direction of movement according to whom you are judging

Generally, we judge the direction of motion by comparing it with the position of the starting point of our motion.

The direction of velocity is the direction in which the particle is now moving.

As for displacement, you need to use the position of the object after movement compared to the position of the starting point.

For example, if the object is moving to the right of the starting point, the direction of the displacement is to the right, but if the object is moving to the left, the direction of the velocity is to the left.

Therefore, the direction of velocity is not affected by the direction of displacement.

The displacement only considers the starting point and the end point, and the process is not considered, and of course there is no such problem for you.

The direction of displacement is the direction of the line from the initial position to the last position.

Velocity refers to the direction in which the position of a particle changes instantaneously.

To put it simply, velocity is a point in time, while displacement is a time period.

Displacements are generally expressed in x, while distances are often expressed in s.

Displacement and distance are two physical quantities with different properties, displacement is a vector quantity, with magnitude and direction, while distance is a scalar quantity, that is, a physical quantity with no direction and only magnitude.

In unidirectional linear motion, the distance is the length of the linear trajectory; In curvilinear motion, the distance is the length of the curve trajectory.

When an object returns to its original position after a period of time during motion, the distance is not zero, and the displacement is equal to zero.

Terminal velocity vs. time: vt vo+at

Displacement vs. time: x=vot+at2 2

Velocity and displacement relationship: vt 2-vo 2 qingjue 2as average velocity v s t;

velocity v(t) (vt+vo) 2=x t;

Intermediate position velocity v(s) [vo 2+vt 2) 2]1 2;

The formula inferences δs at 2;Note: In the equation, δs is the difference between the displacements in the continuous adjacent equal time (t), and this formula is also the principle equation for the acceleration experiment of the dot timer.

The velocity is directly proportional to the displacement, and the deduced conclusions are ridiculous?

A teacher analyzed this point in the class: If the velocity is proportional to the displacement, you can make a velocity-distance image as shown in Figure 1, what is the significance of its slope? The slope represents time.

Since this is a one-time square relationship, the slope is constant, which means that no matter how long it falls, the time is the same, which is obviously not true.

Free fall speed.

First of all, it is necessary to understand the definition of slope. The slope, also known as the "angular coefficient", indicates how much a line is tilted relative to the abscissa axis. As shown in Figure 2, the tangent value of the angle between a straight line and the direction of the positive semi-axis of the abscissa axis of a plane Cartesian coordinate system is the slope of the straight line relative to the coordinate system, and its definition is as follows:

k=tanα=(y2-y1)/(x2-x1)=δy/δx。From this, it can be seen that the teacher's analysis has stolen the concept and has a serious loophole: the slope of v and x in Figure 1 should be k = δx δv, where δx is the change in displacement, δv should be the change in velocity, and δx δv is a unit of time in terms of units, but its ratio is not the motion time of the object.

Free fall speed.

Through the time differentiation of displacement, the motion characteristics of "velocity proportional to displacement" can be derived and analyzed. If v x, then the relationship between velocity and displacement can be written as the equation v=kx, and the differential of displacement to express velocity gets: dx dt=kx, and the separation of x and t variables obtains:

dx x=kdt, the displacement and time are integrated on both sides of the equation to obtain ln(x x0)=kt, x=x0ekt, and further calculation can obtain the velocity and acceleration of the object's motion: v=dx dt=kx0ekt=kx, a=d2x d2t=k2x, it can be seen that according to the above definition of motion, in the process of motion of the object, v is proportional to x, and its acceleration a is also proportional to x, that is, with the increase of v, both x and a increase, There is a positive proportional relationship between k and k2, respectively. And if x0=0, then x, v, and a are all 0 at any time, so it is absurd to draw conclusions.

Later, Galileo himself realized that the assumption that v is proportional to x leads to obvious fallacies, and instead assumes that v is proportional to t, and studies it experimentally and inferentially.

I believe that everyone knows that there are two concepts of displacement and velocity in life, but specifically in physics, what is the relationship between displacement and velocity? In fact, displacement is the accumulation of velocity in time, and velocity is a kind of relative quantity to be precise. In life, the relative position of an object relative to another object changes by the magnitude of the amount of time per unit of time, that is, the magnitude of displacement.

Usually we refer to these two concepts when we describe how much or how fast an object does a certain action in a certain amount of time. Velocity is a type of vector quantity, so velocity is directional. Displacement uses displacement to represent the change in the position of an object (particle).

Defined as: a directed line segment from the beginning position to the last position. Its size is independent of the path, and the direction is from the start point to the end point.

It is a physical quantity with magnitude and direction, i.e., a vector. If an object moves from the initial position to the last position in a certain period of time, the directed line segment from the initial position to the last position is called the displacement. Its magnitude is the straight-line distance from the initial position to the last position of the moving object; The direction is from the beginning position to the last position.

The displacement is only related to the beginning and end position of the object's motion, not the trajectory of the motion. If the particle returns to its original position after a period of time during motion, then the distance is not zero and the displacement is zero.

Let the velocity deflection angle be 1, the displacement deflection angle is 2, and the velocity of the water zen Gao Pinghe trap ruler is vLet the velocity of the particle in the y direction at time t: vy=g*t, so tan 1=vy v=g*t v at this time the horizontal displacement of the particle x=v*t, and the vertical displacement y=, so tan 2=y x=g*t (2*v) Therefore, we can conclude that:

tanα1=2tanα2.That is, the sine value of the velocity deflection angle is 2 times the sine value of the displacement deflection angle. This conclusion is used very often in high school, and you should keep it in mind.

If the direction of motion changes, the direction of velocity must change, the direction of displacement may change, and the direction of acceleration may change.

If the direction of velocity changes, the direction of motion must change, the direction of displacement may change, and the direction of acceleration may change.

If the direction of displacement changes, the direction of motion must change, the direction of velocity must change, and the direction of acceleration must change.

The direction of acceleration changes, the direction of motion may change, the direction of velocity may change, and the direction of displacement may change.