A and B are moving on the same straight line, and their V-T images are shown in a and B respectively A. They move in the same direction. B. they move in the opposite direction. C. they accelerate in the same direction. D. they accelerate in the opposite direction

A and B are moving on the same straight line, and their V-T images are shown in a and B respectively A. They move in the same direction. B. they move in the opposite direction. C. they accelerate in the same direction. D. they accelerate in the opposite direction

A. If the linear velocity of a and B is positive, we know that the motion direction of a and B is the same. Therefore, a is correct and B is wrong. The slope of C and B represents acceleration. If the slope of a is positive and B is negative, we know that the acceleration direction of a and B is opposite. Therefore, C is wrong and D is correct. Therefore, ad is selected

As shown in the figure, the velocity image of two objects moving along the same straight line from the same position
A. When a and B accelerate, the acceleration of object a is less than that of object B. when B. 20s, the farthest distance between objects a and B is C. 60s, and object a is in front of object B. when D. 40s, the velocities of objects a and B are equal, 200m apart

A. In the velocity time image, the slope of the tangent represents the acceleration. The acceleration inclines upward to the right, the acceleration is positive, and downward to the right, the acceleration is negative; so the acceleration of a object: A1 = △ V △ t = 40 − 1020m / S2 = 1.5m/s2, the acceleration of B object: A2 = △ V △ t = 40 − 020m / S2 = 2m / S2, so a is correct, Before the end of 40s, the speed of a is always greater than that of B, and the distance between a and B increases gradually. After 40s, the speed of a is less than that of B, and B begins to catch up with object a, and the distance decreases. Therefore, at the end of 40s, the distance between two objects is the farthest, △ x = XA XB = (10 + 40) × 202m + 20 × 40m-12 × 20 × 40m = 900m, so B is wrong and D is wrong The displacement of a is greater than that of B, that is, a is in front of B, so C is correct

The difference between equal time and any equal time in physics, the relationship between acceleration and velocity
When doing questions, I always don't understand, and I don't understand how to see uniform acceleration and deceleration in V-T images, and what angle degree the teacher said

The equal time and mean are not arbitrary. However, if we say that any equal time, it usually involves the constant acceleration. Acceleration is the rate of change of speed. Acceleration is large, the change of speed is fast, not large. Acceleration is small, the change of speed is slow, and

Is the T-axis in the physical st image represented as displacement 0? A straight line slants down and crosses the 0 point of the S / T axis. What motion is it?
If there is another diagonal line starting from - 1 of the S / T axis, what is the upward movement?

If the straight line slants down, then the object has been going back. Before it exceeds, it means that it has not passed the origin. After it exceeds, it means that it has passed the origin and is still going back. In the S-T image, it is a linear motion

On the direction judgment of time displacement image and velocity displacement image

In the displacement time image, the position of the straight line above the T-axis is positive; when the angle between the straight line and the T-axis is an acute angle, the velocity is positive; when the angle between the straight line and the T-axis is an obtuse angle, the velocity is negative
In the velocity time graph, the straight line above the T-axis indicates that the velocity is positive; when the angle between the straight line and the T-axis is an acute angle, it means that the acceleration is positive; when the angle between the straight line and the T-axis is an obtuse angle, it means that the acceleration is negative

What is the physical meaning of displacement time image? What is the difference between displacement time image and object motion trajectory?

Displacement time image:
It represents the law that the position coordinate X of the moving object changes with time,
It is the image of the functional relationship between the position coordinate X of the moving object and the time t
The displacement time image is an x-t function image, not an object's moving track!

How to judge the moving direction of object in displacement time image
And how to judge the direction of the object in the V-T image

How to judge the moving direction of object in displacement time image: directly see whether the displacement is positive or negative
How to judge the moving direction of an object in V-T image: we need to look at the area of the figure surrounded by the curve and x-axis. Specifically, we need to see whether the algebraic sum of the area above the x-axis and the area below the x-axis (marked as negative) is positive or negative. If the algebraic sum is positive [then the moving direction is positive] or negative [then the moving direction is negative]

Who can tell you how to see the direction of the object's motion from the displacement time image and velocity time image? Thank you

When the slope is greater than 0, the acceleration is equal to 0, the constant speed is less than 0, and the deceleration is less than 0. This is the same direction. The direction of motion depends on the area. The area is above the time axis and goes in the specified positive direction. When the area is below, it goes back. In particular, when the areas on both sides of the time axis are the same, it goes back to the origin

The change chart of speed and time can judge the movement mode of object
According to the graph to determine the movement of the object, how to do it

Speed and time is a straight line, which is a uniform motion. A straight line upward is a uniform acceleration motion. A straight line downward is a uniform deceleration motion. A straight line is a curve, which is a variable speed motion. In short, the trend of a line represents a variable form of acceleration

One of the following statements is true about the displacement time image of object motion in senior one physics
a. The st image represents the functional relationship between the displacement of the particle and time
b. St image is the trajectory of particle motion
c. The coordinates of each point on the st image represent the displacement of the corresponding particle at each time
d. The coordinates of each point in the st image represent the distance that the particle passes through at each time

AC is right