Recalculation power consumption

1. From cheap electricity to centralized mining, China's resources and environment provide bitcoin miners with many advantages. In recent years, bitcoin miners have used cheap electricity to expand their business in coal rich regions such as Xinjiang and Inner Mongolia, which are home to the founders of some of the world's leading mining companies

with the rising price of bitcoin, more and more people join the bitcoin mining business. Accordingly, mining consumes more and more energy. Obviously, our government is also aware of this

according to the requirements of the document, regulators require local governments to take measures related to electricity price, land use, tax and environmental protection to guide bitcoin miners to withdraw from the business. According to foreign media reports, regulatory authorities are mainly concerned about the money laundering and financial risks involved in the shutdown policy, but excessive power consumption is also a factor that can not be ignored. In principle, bitcoin mining consumes a lot of power because every time a new bitcoin is proced, it needs to solve the complex mathematical problems through the encryption process performed by a high-performance computer. Mining calculation process is used to verify bitcoin transactions in the blockchain to ensure security, but the disadvantage is that it consumes a lot of energy.

2. We need the mass m, angular velocity W, radius r of the earth and the distance between the latitude and the earth's center line r
G = GM / RR RWW

3.
(1) Required equipment: balance, spring dynamometer< (2) experimental steps and physical quantities to be measured: < br > ① measure the mass of a hook code m with a balance, < br > ② hang the hook code on the spring dynamometer to measure its gravity g respectively, < br > ③ then G = < table cellpadding = - 1 "cellspacing = - 1" style = "margin"- right:1px ">Gm< Br > (3) calculation expression: g = < table cellpadding = - 1 "cellspacing = - 1" style = "margin"- right:1px ">Gm．

4. Always lose? If you have extra money, help him return it. If you don't, it's hard to help him. But if you help him blindly, he may make more efforts to carry out improper operation. The serious point is to connive him to make mistakes, and he may not know how to repent. So it's hard to decide whether to help or not.

5. A person's standard weight is 60kg, for reference.

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

7. According to the law of universal gravitation,
F lead = g (M1) (M2) / R ^ 2
when f lead is at the equator, = mg
that is, Mg = g (M land) (m) / (r land) ^ 2
it is concluded that g = g (M land) / (r land) ^ 2 = 9.8

in addition,
if f lead is not at the equator,
the combined force of F lead = mg and the centripetal force of the earth's rotation is
so g in all regions is not 9.8

m land = 5.976 * 10 ^ 24kg, R land = 6371004m
G = 6.672 fifty-nine × 10 ^ (- 11) m ^ 3 / kgs ^ 2

your calculator should get 9

8.

1. Gravity anomaly

gravity anomaly is to eliminate the normal gravity part from various factors causing gravity change, so as to obtain the gravity value caused by geological body with different density from surrounding rock. In gravity exploration, the gravity change caused by the uneven density distribution of underground rocks and minerals is called gravity anomaly. However, in the study of the earth's interior, in a broad sense, that is, the difference between the gravity value measured on the ground and the theoretical gravity calculated according to equations (7-37) and (7-38) is called gravity anomaly, that is,

& # 8710; g=g— γ 7-40)

where G is the measured gravity value at the measuring point; γ It is the normal gravity value on this point. Since the measuring point is not necessarily on the normal ellipsoid, it is not necessarily the normal gravity value g < sub > G φ

in the gravity exploration and the study of the earth's internal structure, it is not only based on the gravity anomaly value of indivial points, but on the data of a survey line or an area. At this time, we are interested in the variation of gravity anomaly on a line or a certain area. It is customary to say that there is no gravity anomaly when the gravity anomaly is small or irrelevant to the geological body studied. This method of taking the gravity value of a certain base point as the normal value and comparing the gravity value of other measuring points with it is called relative gravity anomaly value, which has been widely used in ore prospecting

Gravity anomaly and resial mass gravity gravity anomaly in gravity exploration: if the observation is carried out at a certain point a on geoid, and the density of underground rock is uniformly distributed and all of them are normal σ< When sub > 0 < / sub >, its normal gravity is g < sub > 0 φ, when there is a density of σ When the volume of the geological body is V, the geological body has a resial density relative to the surrounding rock; σ， Its size is

, # 8710; σ=σ—σ< Sub > 0 < / sub >

the resial mass of the geological body relative to the surrounding rock is (# 8710; σ· V If its gravity at point a is f, then its gravity at point a should be g < sub > G φ and F. Because g < sub > G φ is 10 < sup > 7 < / sup > g.u., while the maximum value of F is only 10 < sup > 3 < / sup > g.u., so there is little difference between the directions of G and G < sub > e < / sub > and the gravity anomaly at point a is

& # 8710; g=g—g _{φ=F·cos θ}

In

formula θ It is the angle between gravity F and gravity g proced by the resial mass of geological body

The gravity anomaly in gravity exploration is the component of gravity proced by the resial mass of geological body. If the density of the geological body is less than that of the surrounding rock, the resial density is negative and the resial mass is also negative. Of course, the gravity anomaly is also negative

basic formula: take a point o on the ground as the coordinate origin, the Z axis is vertically downward (i.e. along the direction of gravity), and the X and Y axes are in the horizontal plane. If the density difference between geological body and surrounding rock (i.e. resial density) is 0 σ， A certain volume element in geological body DV = D ζ d η d ζ， Its coordinates are ζ，η，ζ， If its resial mass is DM,

DM= σ dv= σ d ζ d η d ζ

let the coordinates of calculation point a be (x, y, z), and the distance between the resial mass element and point a be r:

Introction to Solid Geophysics

according to the gravity potential, the gravitational potential of the resial mass of the geological body to the unit mass at point a is

Introction to Solid Geophysics

where V is the volume of the geological body. Because the direction of Z is the direction of gravity, the gravity anomaly is the derivative of the gravitational potential of the resial mass along the Z direction, that is,

Introction to Solid Geophysics,

if the shape and burial depth of the geological body do not change along the horizontal direction, and extend infinitely along this direction, then the geological body is called the second geological body. The y-axis direction in equation (7-42) is taken as the extension direction of the second geological body, η When the resial density is uniform, it can be mentioned beyond the integral sign, that is,

Introction to Solid Geophysics,

Where s is the cross-sectional area of the two-dimensional body

At the same time, we can dece the basic formula to calculate the vertical gradient of gravity anomaly or gravity vertical gradient anomaly:

Introction to Solid Geophysics

basic formula to calculate the horizontal gradient of gravity anomaly or gravity horizontal gradient anomaly:

Introction to Solid Geophysics

Introction to Solid Geophysics

calculation of gravity The basic formula of anomaly vertical second derivative or gravity vertical second derivative anomaly:

Introction to Solid Geophysics

9. Gravity does work. Don't mix it with other forces
the work done by gravity is equal to the rection of gravitational potential energy.