Is there a direction for the resultant force to be zero, and the resultant force is zero and the res

When the motion of the object is in equilibrium (the direction is unchanged, the velocity is constant), the net force is 0, and the parachutist you said is falling at a constant speed in the air, indicating that his velocity is not equal (the magnitude and direction do not change), and the net force he receives at this time is 0But why did he go down? That's because he has to move, and the resistance of the air can be counteracted by gravity.

So at this point the resultant force is still 0, a force of 0, and its direction is arbitrary.

No. If the effect of several forces acting on a particle together is the same as that of a force f, then this force f is called the resultent force (equivalence).

The direction of force f is the direction of the combined force of several forces.

Force is a vector quantity, and the resultant force refers to the vector sum of multiple forces acting on the same object together. The resultant force is a vector quantity, and the addition and subtraction of vectors satisfies the parallelogram rule and the triangle rule.

The net force is 0 when the velocity decreases.

It contradicts "the resultant force is straight down", so this sentence is wrong.

The resultant force is 0, which is the 0 vector in mathematics, and the direction is arbitrary.

He should be subjected to two forces, and an air buoyancy, or he would have plummeted at a uniform speed.

Or put"Straight down"Changed to"is 0"Or put"The resultant force is changed vertically downward" to "vertically downward, and the resultant force of air buoyancy is 0".

The net force is 0 and the object is at rest. So there is no direction.

The force changes the speed, the speed is constant, the speed does not change, there is no force naturally, the force is 0, there is no direction!

Mathematically, a force with zero resultant force is a zero vector, and the direction of the zero vector is arbitrary.

Note that the skydiver descends at a constant speed in the air, pay attention to the word "constant speed"! ~

Constant velocity means that the resultant force is "0".

Also, the movement of an object does not have to be forceful! ~

There is no force, where is the direction,

The buoyancy and gravity are balanced, and the resultant force is 0, so it is not vertically downward.

See Newton's first law.

Falling at a uniform speed is not affected by force.

There are no orientation issues.

Zero, there is no direction, you yourself "wrap around" yourself. Hehe.

When it's 0, the direction is arbitrary, but everywhere it's 0

The resultant force is zero, and the resultant moment is not necessarily zero.

Suppose that a rod (rigid body) is vertically consolidated on a horizontal plane, and a force in the horizontal direction is applied to the rod, then the force analysis of the rod is carried out.

Because it is a consolidation, it is a statically determined structure, so the net force is zero, but the principal moment is definitely not zero at this time. Suppose there is a shaft in the middle of the disc, which runs vertically into the air, and a force of the same magnitude and opposite direction is applied at the upper and lower ends of the wheel at the same time, and the net force of the disc is also zero.

Knowledge Expansion: A moment is a measure of the effect of a force on an object to rotate around a point or axis. The moment of the resultant force to any point in the plane is equal to the algebraic sum of all its components to the moment of the same point. This theorem is known as the resultant moment theorem.

Resultant moment theorem: In the plane convergence force system, the moment of the resultant force to any point in the plane is equal to the algebraic sum of all its components to the moment of the same point. The role of the moment is to rotate an object around a point or axis in N·meters (n·m).

Suppose a rod (rigid body) is vertically consolidated on a horizontal plane, and a force in the horizontal direction is applied to the rodForce analysisBecause it is a consolidation, it is a statically determined structure, so the resultant force is zero.

In physics, moment refers to the tendency of an object to rotate around an axis or fulcrum of rotation. The unit of moment is Newton.

Rice. Moment Greek letters.

It's tau. The concept of moment originated with Archimedes.

The study of leverage.

Rotational torque is also known as torque or torque. The moment is able to cause the object to change its rotational motion. Pushing or dragging involves applied force, while torsion involves moments. The moment is equal to the cross product of the radial vector and the applied force.

It's important to be clear about the reels:

Most of the time the shaft of the object is easy to determine, but in some cases it is necessary to determine the position of the shaft yourself. For example, a long wooden stick is placed on the level ground, and its two ends are AB, and now it is to the B end.

Add a vertical upward external force so that the rod just leaves the ground, and seek the force f magnitude.

In this problem, the horizontal straight line perpendicular to the rod at point A is the axis of rotation of the rod. In this way, before solving the problem, there are many problems that must first be analyzed to determine the rotating shaft, and the moment can only be calculated if there is a clear rotating shaft in the vertical setting, and then the moment balance condition can be used.

1. The net force is zero means that the object is in equilibrium, and the object remains at rest or moves in a straight line at a uniform speed. Several forces acting on a particle work together to produce an effect, and if it is the same as the imitation effect of a certain force f, then this force f is called the resultant force of several forces.

2. Force is a vector, and the resultant force starts the fiber and refers to the vector sum of multiple forces acting on the same object. The resultant force is a vector, and the addition and subtraction of vectors satisfies the law of parallelograms and the law of triangles.

It's a very common phenomenon.

Suppose a rod (rigid body) is vertically consolidated on the horizontal plane, and a force in the horizontal direction is applied to the rod, then the force analysis of the rod is carried out, because it is a consolidation, it is a statically determined structure, so the resultant force is zero, but the principal moment is definitely not zero at this time.

To take another easy-to-understand example, suppose that there is a shaft in the middle of the disk, which runs vertically into the air, and exerts a force of the same magnitude and opposite direction at the upper and lower ends of the wheel at the same time, then the net force of the disk is also zero, but the moment is not zero. However, if a pair of equal forces are applied in the opposite direction horizontally through the center of the circle, the net force is zero and the moment is zero. Therefore, it is not equivalent to say that the resultant force is zero and the resultant moment is zero.

Force and moment are two different concepts, and there is no necessary relationship between zero net force and zero moment of resultant force.

A pair of parallel forces acting on the same rigid body that are equal in size and in opposite directions, but not collinear, produce a force couple. A force couple is two equal parallel forces whose resultant moment is equal to the product of one of the parallel forces and the distance between the parallel force (called the couple arm), which is called the "couple moment". The couple moment is short for "the moment of the couple".

The resultant force is 0 and is not necessarily collinear.