Haiji-1, developed by China, can withstand a pressure of 7 * 10 to the 7th power, if the density of sea water is 1 * 10 to the 3rd power, If G = 10, the maximum submergence is several meters 500m more than the maximum diving depth of five other submersibles in the world

Haiji-1, developed by China, can withstand a pressure of 7 * 10 to the 7th power, if the density of sea water is 1 * 10 to the 3rd power, If G = 10, the maximum submergence is several meters 500m more than the maximum diving depth of five other submersibles in the world

From P = pGH, H = P / pH = 7 * 10 * 7 / 1.1 * 10 * 4 * 10 = 6363.6 M

We often use the idiom "tip of an iceberg" to describe things that only show a small part of them. In fact, when an iceberg floats in the sea, it really only shows a "tip",
We often use the idiom "tip of an iceberg" to describe that only a small part of an iceberg is exposed. In fact, the iceberg is only exposed when it floats in the sea, and more parts are submerged under the sea. Then, what percentage of the total volume of the iceberg is submerged under the sea? (ρ sea = 1.03 × 1000kg / m3, ρ ice = 0.9 × 1000kg / m3)

Let v be the total volume of the iceberg and V be the volume of the ice submerged under the sea. Then according to the buoyancy formula, the buoyancy of the ice is f = ρ sea * g * V, which is equal to the gravity g of the ice, that is, f = g, that is, ρ sea * g * V = ρ ice * g * V ice, and the two sides of the equal sign are eliminated, so that: ρ sea * V = ρ ice * V ice

An ordinary middle school student in the air, the buoyancy of the air is closest to (the density of human body is close to the density of water, the density of air is 1.29 kg / m3)
The following options are correct:
A 50N
B 5N
C 0.5N
D 0.05N

C
The gravity of the discharged gas is the buoyancy referred to in the title, and the volume of the discharged gas is the volume of human beings
Suppose the density of people is 1g / cm3
Let's say people are 60 kg
g=9.8

The process of measuring and calculating the density of milk
There is a balance, there is no measuring cylinder, you can use other auxiliary equipment

Measure the mass m 0 of beaker with balance, fill it with water, measure the mass m 1 of water and beaker, pour out water, dry the beaker, fill it with milk, measure the total mass m 2 of beaker and milk (fill it twice, ensure the volume of water and milk is equal), then V water = V milk = (M 1-m 0) / P, so the density of milk = (M 2-m 0) / [(M 1-m 0) / P] is = P

How many methods are there to measure the density of small stones?
Please list them succinctly one by one! To be succinct, one or two sentences will do, irrelevant ones will not
1. There are only scales and measuring cylinders
2. Only spring scale and measuring cylinder
3. Only scales
4. Spring scale only
5. Measuring cylinder only
How do you measure the above? Anything else?

1, mass divided by volume
2. Through buoyancy: you can first measure the gravity g of the stone with a spring scale, then immerse it in the water, and read the number F. G: (G-F) = P matter VG: P water VG = P matter: P water

With these data, the calculation process of density can be worked out
A. Weigh the mass of the metal block with a balance, and the result is M1 = 79kg
B. Inject proper amount of water into the measuring cylinder, and use the balance to weigh the total mass of the measuring cylinder and water as M2 = 180g
C. Inject proper amount of water into the measuring cylinder, and the reading of the measuring cylinder is V1 = 50.0ml
D. Put the metal block into the measuring cylinder, and use the balance to weigh the water in the cylinder and the mass of the metal block, m3 = 259G
E. Put the metal block into the measuring cylinder, and the reading volume of the measuring cylinder is V2 = 60ml
The density of the metal block is kg / m3

Metal block is 79g, remove B, D two steps
seven point nine

How to measure the density of small stone with spring dynamometer

1. Measuring the quality of stones
Fill the beaker with water and record the scale
Slowly put in the stone and record the scale
Subtract the two values and multiply by the mass of the specific gravity of water
2. Measuring the volume of stone
Fill the beaker with water and record the scale
Slowly put the stone into the water and record the scale
The volume is obtained by subtracting the two values
Divide by three

The process of measuring and calculating the density of brine
,

Measure the density of brine with balance and measuring cylinder
① Pour an appropriate amount of salt water into the beaker, and measure the total mass M1 of salt water and beaker with the adjusted balance;
② Pour part of the salt water in the glass into the measuring cylinder and read out the volume V of the salt water;
③ By measuring the total mass m2 of beaker and remaining brine with balance, the mass m of poured brine can be calculated;
④ According to the density formula, the density of brine can be calculated

Calculation formula of stone density

p=m/v