Is kinetic energy scalar, is kinetic energy a vector or scalar

It is impossible to be negative while the increment of kinetic energy can be negative.

This is the definition of people, in order to solve certain physical problems. People have summarized some phenomena and found that the physical quantity "mechanical energy" is calculated according to the scalar law, and the conclusions obtained are consistent with phenomena and facts. Momentum is vector and the same is true.

So it's so prescribed. If, one day, it is discovered that physical phenomena can no longer be explained according to such a regulation, they are no longer scalars or vectors.

2.** on the kinetic energy theorem and the momentum theorem.

According to experiments, it has been found that several physical quantities occur in many phenomena in which the product of these physical quantities conforms to a certain formula. So they defined the product of these physical quantities (mass and velocity) as "momentum". Kinetic energy is also similar.

3.And the relationship between the two of them?

The quantity of kinetic energy is equal to the quotient of "momentum squared" and "twice the mass".

4.Why does the Ox 2 law only apply to macro, low speed?

At first, it was found that Newton's laws were consistent with the facts observed at the time, so they were called "laws". Later, one day, when they found that this law was no longer valid to explain high-speed and microscopic physical phenomena, they said that this law was only summarized by previous people from macroscopic and low-speed phenomena, and was not applicable to high-speed and microscopic phenomena. If, however, one day it is discovered that Newton's laws do not apply to a macroscopic, low-velocity phenomenon, they will say that Newton's laws only apply to "some" macroscopic low-velocity phenomena.

5.The teacher said that the momentum in the universe is horizontal, so who gave the initial momentum?

No one can give you a real answer to this question at the moment, the best physicists in the world are guessing, and ordinary people either listen to this physicist or that physicist.

is a scalar quantity. The negative sign on the book indicates "0", that is, the initial kinetic energy is 0, which is equivalent to the increment of kinetic energy with a negative sign in front of it.

Positive and negative in energy: kinetic energy, thermal energy, internal energy, elastic potential energy have no negative values. And the potential energy related to position – gravitational potential energy, mechanical energy, electric potential energy, molecular potential energy, atomic energy level, etc., have negative values.

I'm afraid this brother is wrong, the original words in the book are not like this.

Kinetic energy is a scalar quantity. Gravitational potential energyIt is the work done by gravity of an object with a unit mass moving from a certain high-speed shed to a zero potential surface. Work is the dot product of f and s.

The dot product of two vectors is a scalar quantity. Kinetic energy is a resultant external force.

The work done, the work is the dot product of f and s, the dot product of the two vectors is a scalar or the kinetic energy expression is mv velocity v is the vector, and its square is v and v multiplication! Also scalar.

The kinetic energy expression ek=(mv 2) 2. where m is the mass of the object and v is the velocity of the object.

Gravitational potential energy: ep = mgh. where m is the mass of the object and g is the acceleration due to gravity.

h is the height. Kinetic Energy Definition: The energy that an object has due to its motion, known as the kinetic energy of the object. Its size is defined as one-half of the product of the mass of the object and the square of the velocity.

Impulse

Impulse is the cumulative effect of force on time. The impulse of the force on the object, which causes the momentum of the object to change, and the impulse is equal to the amount of change in the momentum of the object.

In the collision process, the interaction time of the object is very short, but the force is very large, and the force changes very violently in this short time, so it is difficult to accurately measure the force and the acceleration of the object. Moreover, this kind of problem sometimes does not require an understanding of the force and speed at each moment, but only an understanding of the accumulation of force in the time of action and the effect it produces.

The above content reference: Encyclopedia --- kinetic energy.

Kinetic energy is a scalar quantity. Kinetic energy is a type of energy, and its SI system of units.

The lower unit is the joule.

Kinetic energy (and the various works that correspond to it) are scalar quantities, i.e., they have magnitude and no direction. When summing, only its algebraic sum is calculated, and it does not satisfy the parallelogram rule of vectors (called vectors in mathematics).

Kinetic energy theorem. Generally, it only involves the beginning and end states of the object's motion, and the amount of change in the beginning and end states is obtained through the transformation of the rock that can be built during the work done in the process of motion. But the total energy is to follow the law of conservation of energy.

The transformation of energy includes changes in kinetic energy, potential energy, heat energy, light energy, and other energy.

The difference between a scalar and a vector.

In physics, scalar quantities (or pure quantities.

Refers to a physical quantity that remains unchanged under the transformation of coordinates.

In layman's terms, a scalar quantity is a quantity that only has a size in front of the block, and has no direction.

A vector is a quantity that has both magnitude and direction. In general, they are called vectors in physics and vectors in mathematics. In the computer wisdom hu, vector illustration.

It can be infinitely magnified and never deformed.

The above content refers to the Encyclopedia - Kinetic Energy Theorem.

Kinetic energy is vector simplicity, and the direction of kinetic energy is the same as the direction of velocity. in classical mechanics.

, momentum is expressed as the product of the mass and velocity of the object and is a physical quantity related to the mass and velocity of the object.

Refers to the tendency of the object to maintain its motion in the direction of its motion.

The energy that an object has due to its motion is known as the kinetic energy of the object. Its size is defined as one-half of the product of the mass of the object and the square of the velocity. Therefore, for an object with the same mass, the greater the velocity of motion, the greater its kinetic energy; The greater the mass of an object moving at the same velocity, the greater the kinetic energy.

Make use of the kinetic energy theorem.

According to the kinetic energy theorem, if a moving object is hindered and slows down until it stops, the object will do work on the obstacle. The amount of work done is equal to the amount of the original kinetic energy of the object. Hence it can be said that kinetic energy is the action force that an object has due to its motion.

For example, the bullet that flies at high speed has kinetic energy, so it can penetrate the steel wrench when it hits the steel plate; The hammer hammer hammer that is hammered onto the forging has kinetic energy, so it can work on the forging and deform it.

Kinetic energy is a vector quantity, and the direction of kinetic energy is the same as the direction of velocity. In classical mechanics, momentum is expressed as the multiplicative deflection of the mass and velocity of an object, and is a physical quantity related to the mass and velocity of an object, which refers to the tendency of this object to maintain motion in the direction of its motion.

The energy that an object has due to its motion is known as the kinetic energy of the object. Its size is defined as one-half of the product of the mass of the object and the square of the velocity. Therefore, for an object with the same mass, the greater the velocity of motion, the greater its kinetic energy; The greater the mass of an object moving at the same velocity, the greater the kinetic energy it has.

Scalars vs. vectors

In physics, a scalar quantity (or pure quantity) is a physical quantity that remains unchanged under a coordinate transformation. In layman's terms, a scalar quantity is a quantity that has only a magnitude and no direction.

A vector is a quantity that has both a large and a small slow stove and a direction. In general, they are called vectors in physics and vectors in mathematics. In computers, vector graphics can be infinitely enlarged and never deformed.

Momentum only shows the transmission of motion, and kinetic energy can be both transferred and transformed; Momentum is a vector, the change of momentum is related to f and t, kinetic energy is a scalar quantity, and the change of kinetic energy is related to work; If the kinetic energy becomes violent, the momentum will change, and when the momentum changes, the kinetic energy does not necessarily change.

In physics, momentum is a physical quantity related to the mass and velocity of an object. In classical mechanics, momentum (kg·m s in the International System of Units) is expressed as the product of the mass and velocity of an object. Generally speaking, the momentum of an object refers to the tendency of the object to maintain its motion in the direction of its auspicious motion.

Momentum is actually a corollary of Newton's first law. Momentum is a conserved quantity, which is expressed as the sum of momentum within a closed system is immutable.

1. Momentum is a vector quantity, and its direction is the same as the direction of velocity, i.e., p=mv.

2. The impulse is also a vector, and the direction of the impulse is the same as the direction of the force, i=ft, f can be a constant force, or a variable force.

3. The impulse theorem describes the time accumulation effect of force, i=mv2-mv1.

4. The momentum theorem can be directly deduced from Newton's laws of motion, so the momentum theorem and Newton's laws of motion are consistent, and many problems that can be solved by Newton's laws of motion can be solved by the momentum theorem.

5. For a system composed of multiple interacting particles, if the system is not subject to an external force or the vector of the external force is always zero during the force, the total momentum of the system is conserved. It can be expressed as: m1v1+m2v2=m1v1'+m2v2'．

1.The description objects are different. Momentum describes moving at a constant velocity, and kinetic energy describes moving at variable speed.

2.The calculation formula is different. The formula for momentum: p mv, the formula for kinetic energy: e mv2 2.

3.The unit of measurement is different. The unit of momentum is kilograms·meters and seconds, and the unit of kinetic energy is kilograms·(meters)2.

4.The conversion is different. The momentum conversion is instantaneous and the kinetic energy conversion is continuous.

5.The reasons for the change are different. Impulse is the cause of the change in momentum, and work done is the cause of the change in kinetic energy.

6.The metrics are different. Impulse is a measure of the change in momentum of an object, and work is a measure of the change in kinetic energy.

7.The laws of conservation are different. Momentum obeys the law of conservation of momentum, and kinetic energy obeys the law of conservation of energy.

Momentum is a physical quantity that describes the state of motion of an object, whereas kinetic energy is a physical quantity that describes the energy of an object's motion.

1.Define the concept of slippery world

Momentum is a measure of the state of motion of an object, which is the mass multiplied by the velocity, which represents the inertia of the motion of the object and the change of force. Kinetic energy is the amount of energy that an object has due to its motion, which is half of the mass multiplied by the square of the velocity, and is commonly used in physics to describe the energy state of an object.

2.Physical implications

Momentum is related to the motion and interaction of an object and can be used to describe the change in the state of motion of an object and the transfer of force. The greater the momentum, the stronger the motion state of the object, and the greater the inertia under the action of the same force of the judging limbs. Kinetic energy is the energetic manifestation of the motion of an object, depending on the mass and velocity of the object.

3.Expressions and units

The expression for momentum is p=mv, where p is the momentum, m is the mass of the object, and v is the velocity of the object. The unit is kilogram·meter seconds (kg·m s). The expression for kinetic energy is k=1 2mv 2, where k is kinetic energy, m is the mass of the object, and v is the velocity of the object.

The unit is joules (j).

4.Based on quality and speed

The magnitude of momentum is directly proportional to the mass and velocity of the object, i.e., the greater the mass and velocity, the greater the momentum. And the magnitude of kinetic energy is proportional to the square of the mass and velocity of the object, that is, the effect of velocity on kinetic energy is more significant, and when the velocity increases, the kinetic energy increases faster.

5.Variation and conservation

Momentum can be changed by the action of force, according to the momentum theorem, the amount of change in force is equal to the amount of change in the momentum of the object. Whereas, kinetic energy can be changed by the change in the velocity of an object, and when the velocity increases or decreases, the kinetic energy increases or decreases accordingly. In interactions, momentum is conserved, meaning that the total momentum remains constant before and after the interaction; Whereas, kinetic energy is not necessarily conserved, and in cases such as inelastic collisions, kinetic energy is converted or lost.

6.Fields of application

Momentum has a wide range of applications in the field of mechanics and dynamics to explain phenomena such as acceleration, rotation, collision, and force transfer of objects. The momentum theorem is a generalization and application of Newton's second law. Kinetic energy plays an important role in the fields of energy conversion and transfer, as well as mechanical engineering, which can calculate the mechanical energy, work done, and sliding friction of an object.

7.Mutual relationship

There is a certain correlation between momentum and kinetic energy. During motion, when the velocity of an object changes, both its momentum and kinetic energy change. Momentum can be expressed in terms of kinetic energy, i.e. p= (2mk) and vice versa.

But they differ in definition and description, focusing on different physical quantities.

Summary:

Momentum and kinetic energy are both physical quantities that describe the motion characteristics of an object, but there are differences in their definitions, physical meanings, expressions, units, and laws of change. Momentum is mainly used to describe the state of motion and interaction of an object, whereas kinetic energy is mainly used to describe the moving energy of an object. Understanding and differentiating between these two concepts is important for a deeper understanding of object motion, interactions, and energy transitions.