Senior 1 Physics can t understand the meaning of the word straight line 2 in Uniform Linear Motion

Is the floor of your house spherical? Why do we talk about sea level and not hear people say about sea sphere?

The reason is simple, the earth is so big that it is acceptable for us little humans to approximate it as a flat type.

By the way, approximation is a very common method in the study of physics, and it can even be said that it is an important idea.

However, it is still quite good to drill the tip of the horn once in a while

In a frame of reference, objects move in orientation (without changing direction), and if you are on Earth, you can see the Earth as immobile and other objects move in a relatively straight line.

You are a person who loves to study and think very carefully, but you must know that in fact, you should not delve too deep into a lot of physics knowledge that we learn in middle school, and think from the scope of normal understanding, which is very beneficial to you.

This straight line refers to the fact that we use the stationary ground as a reference frame to do linear motion, if you think that the earth is circular, not a straight line, then it is too careful, the radius of the earth is so large, relative to the short length of our usual motion, it can be regarded as a straight line, and the arc is very small

This is also relative, according to you, it is true that it is not a linear motion, but how can the motion of an object be compared with the autobiography of the earth, if I remember correctly, in the inertial coordinate system, the earth's own motion should not be considered.

The topic should be even acceleration!

Solution: Let the acceleration be a, v2=2+2a, v3=2+3a;

So [(v2+v3) 2]*1=;

a=1m/s.

Your first sentence was wrong, if you want to calculate. You can subtract the displacement of the first two seconds from the displacement of the first three seconds, and you're fine

How can an object moving in a straight line with a uniform velocity have an acceleration? If it is a linear motion with uniform acceleration, it is 5 7.

I did this by displacing in the 3rd second, which means that the velocity at the second is and the acceleration is (

How can an object moving in a straight line with uniform velocity have acceleration.

How can an object moving in a straight line with uniform velocity have acceleration?

An object moving in a straight line at a uniform speed?

You have a problem with your topic!

Alas, why do people always make typos? . .

。The brake must be the closest in the first second, slightly smaller than the instantaneous speed (classmate, you don't know what the brake handle is, just make it stop).

This is a uniform deceleration motion, and the acceleration is minus 1. What do you mean?

I haven't touched physics for several years, I have mastered linear motion with variable speed, force analysis, bull one cow two cow three, momentum theorem, kinetic energy theorem, light circuit diagram (refraction, reflection, imaging) series and parallel circuit analysis and calculation of voltage, current, power, voltage division, shunt, electromagnetism, right-hand responsibility, left-hand responsibility, magnetic inductance line, generator principle (high school has learned gravity?) ）

1.Motion is relative, for example, if you analyze a person sitting on a moving car, if you choose the tree next to it as the frame of reference, then the person is moving; Conversely, if the tree is analyzed, using the car as a frame of reference, then the tree is also in motion relative to the car. That is to say, the movement of trees and people is the same after using each other as a frame of reference.

This is the relativity of motion. The same is true for this question.

2.An object can be considered a particle if it is translational or if the size of the object is much smaller than the linearity of its range of motion.

A solar eclipse is a process in which the sun is gradually blocked by the moon, which is related to the shape (linearity) of the sun, and the sun cannot be regarded as a particle.

b The revolution of the earth refers to the rotation of the earth around the sun, which is much larger than the earth, and the earth and the sun are far apart (linear), so the earth can be regarded as a mass point.

c When the earth rotates, it is the movement of the earth's points that is studied, so it is not regarded as a particle.

For example, if we study the size of an atomic nucleus, can we look at it as a particle? Apparently not, why? I thought that if I looked at it as a particle, how could I study its size!

Particle is a point of quality, to judge whether it can be regarded as a point of mass is to see what is studied, such as studying the movement of the train from Beijing to Shanghai, although the train is very long, but for the example of Beijing to Shanghai, the length of the train can be ignored, so at this time the train can be regarded as a point of quality, but it is also a train, if you study the time taken by the train to cross the bridge and other problems, the length of the train can not be ignored, so it cannot be regarded as a point of particle. In layman's terms, your research involves the nature of the object you are studying, such as length, width, or the motion state of the object you are studying, such as studying its own rotation, etc., it cannot be regarded as a particle, a particle is a point, how can a point have length, width, and rotation? Judging the particle is what you want to study rather than the size of the research object, as I just said, the train is very large, it can still be regarded as a particle, and in the same way, if you study the situation of the nucleus itself, although it is small, it cannot be regarded as a particle, because the point itself is not a case, and the point is a point.

The first question, since you don't understand, you might as well find three objects to swing and see, the moon is a reference frame, the moon does not move, you can see if the earth is rotating.

The acceleration of an object is proportional to the resultant force f experienced by the object, inversely proportional to the mass of the object, and the direction of acceleration is the same as the direction of the resultant force, f a, f m, which can be written as f=kma by mathematical expression, where k is a constant. However, since the magnitude of the force of 1 unit was not specified at that time, we took k=1, and we had f=ma,

First, the object moves in a straight line; Secondly, the object moves with constant acceleration, and "uniformity" is reflected in the constant acceleration; Thirdly, the acceleration of the object is in the same direction as the velocity, i.e., accelerating motion. The sum of the three points is "uniform acceleration linear motion".

vt=v+at velocity rule.

x=vt+( at displacement law.

There are two meanings, one is that objects move in a straight line. Second, the object keeps a certain acceleration constant.