How to find the instantaneous speed in high school physics Let s talk about it in detail

In kinematics, if an object moves in a straight line with uniform variable speed, there are three basic formulas for instantaneous velocity:

v(t)=v(0)+at

v(t)]^2-[v(0)]^2=2as

v(average) [v(0)+v(t)] 2=s t In a uniform circular motion, v=s t= r

In kinetics, the instantaneous speed of a motor vehicle when it is started or moving at a constant power.

v = p f, where p is the power of the vehicle and f is the traction force.

The instantaneous velocity can be found from the kinetic energy theorem: w mv2 2 2-mv1 2 2 The instantaneous velocity can also be found from the momentum theorem: ft=mv'-mvThe instantaneous velocity of two or more objects when they interact is found by the law of conservation of momentum.

m1v1'+m2v2'=m1v1+m2v1 If you carefully understand the meaning of instantaneous velocity and understand the relationship between instantaneous velocity and momentum and energy, you will naturally be able to determine the method of solving instantaneous velocity.

Good luck!

The derivative of the displacement corresponding to a specific time is calculated, and then the derivative is evaluated on the corresponding value of a specific time, and the result is the instantaneous velocity.

Derivatives in mathematics can be found.

It depends on the specific problem to solve.

Instantaneous speedThe formula is: v=x t.

1. v=x t (t is infinitely close to 0), instantaneous velocity, is the ratio of the displacement of the adjacent infinite short time at that moment to the time taken through this displacement v=x st, which represents the velocity of an object at a certain time or passes through a certain position. Instantaneous velocity is a vector quantity that has both magnitude and direction. Instantaneous velocity is a quantity in an ideal state.

2. The velocity of a moving object at a certain time or position is called instantaneous velocity, which indicates the velocity of a moving object at a certain time or position. Instantaneous velocity is a vector, and the direction of the instantaneous velocity at a certain moment (or through a certain position) is the direction of the motion of the object at that moment (or through a position).

If the object moves in a straight line at a uniform speed.

His velocity remains constant during the movement, then his instantaneous velocity at any moment and the average velocity of the entire motion process.

It's the same. Instantaneous velocity is a vector quantity, and in linear motion, the direction of instantaneous velocity is the same as the direction of motion of the object, and its magnitude is called instantaneous velocity.

Significance of instantaneous velocity:

In order to accurately describe the linear motion of variable speed is done.

The speed of the particle motion and the direction of motion, we use the method of infinite micro gradual approximation, that is, the average velocity of the particle above the segment is obtained by taking the displacement of the particle through a certain point in the back of a short section, and the smaller the displacement taken from the point, the smaller the change in the velocity of the particle in the period of time, that is, the movement of the particle in the period of time tends to move in a uniform linear line.

When the displacement is small enough (or the time gap is short enough), the movement of the particle during this time can be considered to be uniform, and the average velocity obtained is the instantaneous velocity of the particle through the modification. For variable speed linear motion, the instantaneous velocity at each point is variable.

v0 is the initial velocity, and vt is the final velocity.

v=v0+at

v^2-v0^2=2as

The instantaneous velocity of the intermediate moment v=(v0+vt) 2=s tThe instantaneous velocity of the intermediate displacement v= (v0 2+vt 2) 2

If the time is a linear motion with a uniform variable speed, the velocity at the intermediate moment is equal to the average velocity. If the displacement from the third second to the fifth second is known, the instantaneous velocity of the fourth second is equal to the average velocity from the third second to the fifth second, and the bits from the third second to the fifth second are removed by 2 seconds.

The velocity of a moving object at a certain moment or position is called instantaneous velocity, or velocity for short. Instantaneous velocity is a vector quantity, and the direction of the instantaneous velocity at a certain moment (or through a certain position) is the direction of the object's motion at that moment (or through a certain position). If the object moves in a straight line at a uniform velocity, and its velocity remains the same during the motion, then its instantaneous velocity at any moment and the average velocity of the whole motion process are also the same.

The calculation formula is different for different forms of exercise.

1. If it is a uniform motion, the instantaneous speed remains unchanged.

2. If it is a linear motion with uniform variable speed, the formula is: V(T)=V0+AT.

3. If it is a free fall movement: v(t)=gt.

4. If it is an upward throwing motion: v(t)=v0-gt.

5. If it is a downward throwing motion: v(t)=v0+gt.

6. If it is a flat throwing motion: it is necessary to use the parallelogram rule to decompose and then find the combined velocity.

v(t) = root number [v0 square + (gt) squared].

Instantaneous velocity refers to the velocity at a certain point. Generally, the instantaneous velocity at a certain point in time can be obtained by deriving the distance from the time, and then substituting it at a certain point in time. Instantaneous velocity is a vector quantity that has both magnitude and direction. Instantaneous velocity is a quantity in an ideal state.

Linear motion with uniform velocity: The average velocity of an object in the time interval from t to t + t is s t, and if t is infinitely connected and close to 0, it can be considered that the state represented by s t is the velocity of the object at time t. In a linear motion with uniform speed, the average velocity of a certain period of time is equal to the instantaneous velocity at the intermediate moment (i.e., the instantaneous velocity at the intermediate moment).

Normal Motion: Only estimates can be found. Extend to the left and right sides for a period of time x t tending to 0.

Constant velocity: The average velocity is the instantaneous velocity. The speed of a uniform linear motion is the average velocity.

Instantaneous velocity is referred to as velocity (usually referred to as average velocity), but when the word "speed" is encountered in problem solving and academics, it refers to instantaneous velocity unless otherwise specified. Theoretically, the instantaneous velocity is only an estimate, and the exact calculated time should be infinitely close to 0, but not 0.

Direction: The direction of the instantaneous speed book vertical handicap, that is, the tangential direction of the point's motion on the trajectory.

Instantaneous velocity and average velocity: In linear motion with uniform velocity, the average velocity of the motion of the object is equal to the instantaneous velocity at intermediate moments.

There is no formula for instantaneous velocity, and in the high school range, if the question says that instantaneous velocity is required, it is either that the velocity is 0. Either that, it's an approximation of instantaneous velocity using the average velocity (similar to a dot timer). Uniform speed linear motion:

The average velocity of an object in the time interval from t to t+ t is s t, and if t is infinitely close to 0, it can be assumed that s t represents the velocity of the object at time t.

The calculation formula is different for different forms of exercise.

1. For example, Wang Yinguo is moving at a uniform speed, and the instantaneous speed is unchanged;

2. If it is a linear motion with uniform variable speed, the formula is: V(T)=V0+AT.

3. If it is a free fall motion: v(t)=gt;

4. If it is an upward throwing motion: v(t)=v0-gt.

5. If it is a downward throwing motion: v(t)=v0+gt.

6. If it is a flat throwing motion, it is necessary to use the parallelogram rule to decompose, and then trap the cultivation banquet to find the conjunctive velocity: v(t) = root number [v0 square + (gt) square.