What are Newton's three laws?

Newton's three laws are important laws in mechanics, which are the basis of studying classical mechanics
1. Newton's first law
Content: any object remains stationary or moving in a straight line at a constant speed until it is forced to change this state by the force of other objects
Explanation: all objects have the tendency of keeping still and moving in a straight line at a constant speed. Therefore, the motion state of an object is determined by its motion speed. Without external force, its motion state will not change. This property of an object is called inertia. So Newton's first law is also called inertia law. The first law also clarifies the concept of force. It is clear that force is the interaction between objects, It is pointed out that force changes the motion state of an object. Because acceleration describes the change of the motion state of an object, force is related to acceleration rather than speed. If we don't pay attention to this point in our daily life, it is easy to produce illusion
Note: Newton's first law does not hold in all reference frames. In fact, it only holds in inertial reference frame. Therefore, whether Newton's first law holds or not is often regarded as the criterion of whether a reference frame is inertial reference frame
2. Newton's second law
Content: the object will produce acceleration under the action of combined external force. The direction of acceleration is the same as that of combined external force. The magnitude of acceleration is directly proportional to the magnitude of combined external force and inversely proportional to the inertial mass of the object
The second law quantificationally describes the effect of force and quantifies the inertia of an object. It is vector and instantaneous
It should be emphasized that the external force on the object will produce acceleration, which may change the motion state or speed of the object, but this change is related to the motion state of the object itself
In vacuum, because there is no air resistance and all kinds of objects are only subjected to gravity, they all have the same acceleration regardless of their mass. Therefore, when they fall freely, their velocity changes are the same in the same time interval
Newton's third law
Content: the force and reaction between two objects are equal in size and opposite in direction on the same straight line
Explanation: in order to change the motion state of an object, there must be other objects interacting with it. The interaction between objects is reflected by force, and the effect of force is mutual

What are the three laws of Newton

Newton's first law (the law of inertia) content statement 1: any object in the absence of external force or by the role of equilibrium force (Fnet = 0), always maintain a static state or uniform linear motion state, until there is an external force acting on it to force it to change this state

How to prove the microscopic expression of current I = NESV?

The electric quantity flowing through the cross section in unit time, I = nesvt, t = 1

Max=((a>b?a:b)>c)?(a>b?a:b):c;

（a>b?a:b)>c）
If a > b
Return a, otherwise return B
If the first one returns a, it is compared with C
If a > C
Returns the values compared in a > b? A: B
Otherwise, return C

The resistance of a conductor made of the same material with equal cross-sectional area but unequal length is proportional to its length L

For example, two copper wires of the same thickness, one with length a and resistance RA, the other with length B and resistance RB
Then the resistance ratio of the two copper wires is RA: RB = A: B

If there is a definition: int, I, J, * pi = & I; then the equivalent comparison expression with I = = J is____________
A. i==pi
B. pi ==*&j
C. i==&j
D. i==**pi

B.*pi ==*&j

What does 1000F mean in the expression?
string resultValueString = resultValue.ToString ();
if (resultValue == 1000f)
{ ******}
What is the explanation of "1000F" in the above expression?

F means hexadecimal

In the circuit shown in the figure, the electromotive force of the power supply is e, the internal resistance is r, close the switch s, increase the resistance of the variable resistance R, and the change of the ideal voltage representation is △ U
A. The voltage at both ends of resistance R1 decreases, and the reduction is less than △ UB. The charged capacity of capacitor decreases, and the reduction is equal to C △ UC. The ratio of indication U of ideal voltmeter to indication I of ideal ammeter increases, and the ratio of variation △ U of ideal voltage indication to variation △ I of ideal current indication remains unchanged

AB, close the switch s, increase the resistance value of the variable resistance R, the current in the circuit decreases. According to the analysis of Ohm's law, the voltage at both ends of the resistance R1 decreases, the voltage at both ends of the resistance R increases, and their total voltage, that is, the terminal voltage increases. Therefore, the voltage reduction at both ends of the resistance R1 is less than △ u, and the charge of the capacitor decreases, and the reduction is less than C △ U According to Ohm's law of closed circuit, u = E-I (R1 + R), according to mathematical knowledge, △ u △ I = R1 + R, remains unchanged. So D is correct. So ACD is selected

All the formulas in the first and second chapters of PEP senior high school physics compulsory I
It should be detailed and complete

Senior high school physics compulsory 2 Chapter 1 Formula
There is no problem with the formula. The main ones are (GMM) / R ＾ 2, m * (V ＾ 2 / R) and so on. In these formulas, which R refers to the radius of the central celestial body and which refers to the radius of the motion orbit of the celestial body? The more you say, the more detailed the better

Only in the binary problem, R is different, and the rest is the orbital radius

What are Newton's three laws?