The formula of calculating force

1.

1. Gravity g = mg

(vertically downward, g = 9.8m/s2 ≈ 10m / S2, the action point is at the center of gravity, applicable to the earth surface)

2. Hooke's law f = KX

{along the recovery deformation direction, K: stiffness coefficient (n / M), X: deformation variable (m)}

3. Sliding friction force F = μ FN

{opposite to the relative motion direction of the object, μ： Friction coefficient, FN: positive pressure (n)}

{rrrrrrr}

extended data:

different classification of force

1. According to the nature of force, it can be divided into gravity, universal gravitation, elastic force, friction force, molecular force, electromagnetic force, nuclear force, etc Note that gravity is not equal to gravity under all conditions Gravity does not point to the center of the earth under all conditions. Gravity is a component of the earth's gravitational force on an object, and the other component is a centripetal force. Only on the equator does gravity point to the center of the earth.)

According to the effect of force, it can be divided into tension, tension, pressure, supporting force, power, resistance, centripetal force, restoring force, etc

According to the research object, it can be divided into external force and internal force

According to the action mode of force, it can be divided into non-contact force (such as gravitation, electromagnetic force, etc.) and contact force (such as elastic force, friction force, etc.)

There are four basic interactions (forces): gravitational interaction, electromagnetic interaction, strong interaction and weak interaction

nature of force:

materiality: force is the effect of an object (matter, mass) on an object (matter, mass). When an object is subjected to a force, another object must exert this effect on it. Force cannot exist independently without an object

interactivity (interaction): the interaction between any two objects is always mutual, and the object exerting the force must also be the object under the force. As long as one body exerts a force on another, the stressed body in turn will surely add a force to the exerted body Generating conditions: the force is equal in size (the resultant force is zero, in a state of non directional static motion) or not equal, in the opposite direction, acting on two different objects, and acting on the same straight line. It can be summarized as: foreign body, equivalent, reverse, collinear. A pair of interaction forces must proce and disappear at the same time.)

Vectoriality: force is a vector, which has both magnitude and direction

simultaneity: the force proced and disappeared at the same time

independence: the effect of one force does not affect the effect of another

includes three elements: the size, direction and action point of the force. The accurate expression of the three elements of force by a directed line segment is called the diagram of force. The size is represented by the length of a scaled line segment, the direction is represented by an arrow, the point of action is represented by an arrow or the tail of an arrow, and the straight line along which the direction of a force follows is called the line of action of a force. The diagram of the force is used for the calculation of the force. When the judgment power is large, we must pay attention to the scale of the line segment, because even if one line segment is longer than another line segment, but the scale of the long line segment is also longer, the force represented by the short line segment is not necessarily smaller than that represented by the long line segment

2. Newton's second law of motion: force = mass × Acceleration, force must know mass and acceleration

3. I think if we only know volume and velocity, we can't find the force. i 'm sorry!

4. P = f / s
F = ps
when the object is flat on the table, the pressure is equal to gravity
F = g
liquid pressure formula
P = liquid density * g * H (depth)

5. It's kg! International system of units!

6. ∵ floating
∵ f floating = g = mg = 1kg * 10N / kg = 10N
volume of object v = m / P = 1kg / 0.6 × 103
kg／m3≈0.002m³
buoyancy when the object intrudes into the water
F floating = P water GV row = 20n
no force analysis was carried out before the force was applied to the object
the object received 10N gravity and 10N buoyancy. If the force was applied to make it completely submerge, the buoyancy was 20n
and there was 10N gravity
so 10N buoyancy was applied

7. Gravitation is about equal to gravity, so GMM / R ^ 2 = mg, so
G = GM / R ^ 2

8. I'll teach you the high throw formula: screen distance + / - wind force multiplied by 2 (90 formula value = angle) and then 100 force
if it's a decimal, round it, but add or subtract force accordingly.

9. This is a technical problem

10. (1) The power formula of work done by external force F is p = w / T = f * V
(2) the average power of work done by pulling force F is p = f * V
where V is the average speed of moving object
the instantaneous power of work done by pulling force F is PT = f * VT
where V is the instantaneous speed of moving object