What is the situation that the forces on the crane can often be simplified?

The position of the crane can be reduced to action and reaction forces, which are considered because they are the same two forces.

The force on the crane can often be simplified to the plane parallel force system, and its balance equation is simpler than the plane general force system, and the plane parallel force system can be regarded as a special case of the plane general force system.

The force experienced by the crane can be reduced to the force mass of the object of the crane cable is also heavier.

Because this force can be dissolved, but this should only be done if he is fully able to bear it.

If you want to simplify the force on the crane, then it is directly expressed by a number, and an n can be added at the end, because n represents Newton, and Newton is a unit representing force.

The external load of the crane comprises four parts: lifting load, inertia load, wind load, etc., crane. There will also be multiple iterations.

In the case of the system in the base acceptance ability can speak about why, the immediate atmosphere of the crane is generally the pulling force for it and the upward force is the largest.

If it is a physical calculation, it will be simplified directly, and many other factors are not considered.

What is the situation usually simplified by the forces on the crane? The force on the crane is generally caused by gravity and tension. constituted.

The force on the crane can be reduced to a simple situation.

The tensile force on the crane can simplify the situation, and I think this depends on the genetic situation.

There are indeed very few simplifications around the starter, and it is very simple, if he will win, he will win, and there are a lot of speeches, and they are separated.

The force on the crane can often simplify the situation, what is the situation, I don't know, what is in it.

The force on the crane can often be drawn, and it can be transformed, but I don't know why this is the case.

The object rises, that is, the direction of velocity is upward, and the pulling force is less than the gravitational force, that is, the resultant force of the pulling force and the gravitational force is downward, and the direction of the resultant force is opposite to the direction of velocity, then the object will do deceleration motion.

— Manuscript ———

The net force is zero: the object is at rest or in a straight line at a uniform speed.

The resultant force is in the same direction as the velocity: accelerates in a straight line.

The resultant force and the velocity are reversed: decelerate in a straight line.

The resultant force is not zero and is neither in the direction nor in the opposite direction of the velocity (i.e., not in the same straight line): curvilinear motion.

Answer]: C crane in the process of hoisting heavy objects in the process of transporting the Li Jia Dong book, to produce inertial load, it is customary to call this inertial load the dynamic load.

When the crane lifts heavy objects, the wire rope is not pulled off because it has sufficient stiffness.

It's not stiffness, it's strength, and since the wire rope has strength, it won't be pulled off. The wire rope is a spiral steel wire bundle that twists the steel wire with mechanical properties and geometric dimensions according to certain rules, and the wire rope is composed of steel wire, rope core and grease. The wire rope is a rope that is first twisted into strands by multiple layers of steel wires, and then twisted into a spiral rope by a certain number of strands with the rope core as the center.

In material handling machinery, it is used for lifting, pulling, tensioning and loading. Friend, if it helps you, please give a thumbs up, thank you.

When the crane lifting moment is time, its rated lifting capacity is, and what is its working range.

Hello dear! Rated lifting capacity = crane lifting bucket material moment pulley radius According to the above formula, when the crane lifting moment is 294kn m, its rated lifting capacity should be, so the pulley radius should be 294. The working amplitude refers to the maximum amplitude that the crane can achieve, generally there are full width and half width, the full width refers to the farthest point from the center of the pulley, and the half width refers to the farthest point that can reach half of the center of the pulley.

So when the crane lifting moment is 294kn m and the pulley radius is 12m, its maximum working amplitude is 24m and the half width is 12m. In addition, the rated lifting capacity of the crane is affected by many factors, including frame structure design, motor power, wire rope weight, etc. In addition, its use requires that the use site is flat, free of obstacles and lack of objects, and it should be regularly inspected to ensure that it is safe and reliable.

The object is raised at a constant speed, by the equilibrium condition: f=g=

N The tensile work of the steel rope: wf

FH = work done by gravity: wg

gh = work done by the object overcoming gravity: w = -wg

The total work done by these forces is: w total. wfwg

A: The tension of the steel rope is done.

J's work; Gravity did.

J's work; The object overcomes gravity to do work.

j, the total work done by these forces is 0

The work done to overcome g is 5*2*10 4=10 5(j).

Force analysis: If the object receives two forces and has a uniform velocity, then the pulling force = gravity. The work done by pulling force is 5*2*10 4, and the work done by gravity is.

5*2*10^4。So the total merit is 0j.

The object rises, that is, the direction of velocity is upward, and the pulling force is less than the gravitational force, that is, the resultant force of the pulling force and the gravitational force is downward, and the direction of the resultant force is opposite to the direction of velocity, then the object will do deceleration motion.

— Burning the ———

The net force is zero: the object is at rest or in a straight line at a uniform speed.

The resultant force is in the same direction as the speed: accelerate the straight cherry blossom section to cross the line.

The resultant force is reversed to the velocity: decelerates in a straight line.

The resultant force is not zero and is neither in the direction nor in the opposite direction of the velocity (i.e., not in the same direction and not in a straight line with the same ridge): curvilinear motion.

Hello. You hesitate between b and c, let me analyze it, after reading the question, I know that this question is to tell you the state of motion (uniform deceleration and decline) to find the work done by the wooden box to overcome the tensile force of the steel cable, in fact, it is to find the tensile force of the steel cable, that is, to know the state of motion to find a certain force of the problem.

First of all, the force is analyzed through the motion state of the object, and the uniform velocity decreases, indicating that the resultant force should be upward (the acceleration is also upward), so the tensile force is greater than the heavy force.

You may ask: why does the object still go down? Since the object has a downward velocity, then you ask: what is the use of the resultant force going upward? The upward resultant force causes the downward velocity of the object to gradually decrease, which is the effect of the upward resultant force on the motion of the object).

Then, let's analyze the force of the object (which is already relatively simple): upward tension, downward gravity, upward resultant force, equation f-mg=ma, and the magnitude of the solution f.

Finally, I will talk about this work, he is asking about the work done by the wooden box to overcome the tensile force, this work is a positive work, you will ask why it is positive? If you think that the object is moving downward, and the pulling force pulls it on it and does not let it go down, then the bad guy of the pulling force does negative work, so the object overcomes the pulling force and does positive work. The magnitude of the work can be calculated by multiplying the tension by the distance, and it is OK because it is positive.

Relate. The work done by the pulling force is the displacement of the pulling force multiplied by its direction.

Therefore, because the wooden box decelerates and decreases uniformly with acceleration a, that is, the acceleration is opposite to the direction of velocity, and the direction is upward.

Therefore, the direction of the resultant force is upward, so f pull-mg=ma

The solution yields f pull = m(a+g).

As the displacement of the object in the direction of tensile force is -h

Therefore, the work done by tensile force w=-m(g+a)h

That is, to overcome the tensile force of the steel cable, the work is m(g+a)h, so C is selected