The pressure of water (with "Zhejiang Education Press, Grade 8, Volume 1, science homework a" coming in (1220:59:3) The pressure of water (2) question 11 Xiao Ming used a bottle of pure water and a sponge on a horizontal table to study the "factors affecting the effect of pressure" What is the quality of this bottle of pure water

The pressure of water (with "Zhejiang Education Press, Grade 8, Volume 1, science homework a" coming in (1220:59:3) The pressure of water (2) question 11 Xiao Ming used a bottle of pure water and a sponge on a horizontal table to study the "factors affecting the effect of pressure" What is the quality of this bottle of pure water

It's page eight!
The solution M = PV
=1g/cm^3*600cm^3
=600g
A: the quality of this bottle of purified water is 600 grams

Water pressure (2)

It's a bit troublesome, so I won't talk about the process of application questions. I just talk about the answers
1.A
2.D
3.C
4.A
5.B
6.34 M
7. (1) 980 PA 1.96n (2) 4N 2000Pa
8. A minimum B maximum C medium
9.A
10.D
11.500,700,1200,2200,2200

The pressure of water
An elephant weighs 6 × 10 ^ 4N, and the contact area between the sole of each foot and the ground is 600cm ^ 2. When the elephant raises two feet, the pressure F and pressure P on the ground are calculated
Known
seek
Format

Known: g = 6 × 10 ^ 4 n s foot = 600 cm ^ 2
Find F P
When you raise your foot, gravity is constant, g = f, f = 6 × 10 ^ 4 n
P=F/S
S = 2S foot = 1200cm ^ 2 = 0.12M ^ 2
P = 5x10 ^ 5 Pascal with data

Who has the pressure of saving water in science exercise book a (2)
For the right answer, not the website, the best answer is correct, I thank you, help me spread

The smaller the stress area is, the greater the pressure is. The greater the pressure is. The greater the pressure is. 5. The pressure is placed vertically 6. C7. C8. (1) when the stress area is fixed, the greater the pressure is

On the density of water,
1. In the experiment of "measuring the density of brine", there are the following steps: ① measure the total mass of brine and beaker with tray balance; ② pour part of brine into the measuring cylinder and read out the volume of brine in the measuring cylinder; ③ measure the mass of beaker and remaining brine with tray balance; ④ calculate the density of brine
A.①②③④ B.④①②③ C.②①③④ D.③①②④
2. Only the measuring cylinder, take out 21g gasoline (the density of gasoline is 0.7 × 10 cubic kilogram / cubic meter)
A. Measure the gasoline volume of 7 cubic centimeter in the measuring cylinder B. measure the gasoline volume of 21 cubic centimeter in the measuring cylinder C. measure the gasoline volume of 30 cubic centimeter in the measuring cylinder D. It can't be done by using the measuring cylinder alone, it must use the balance
3. there is a strange perfume bottle. In order to measure its volume, a student used tray balance to measure the quality of the empty bottle is 62.5 grams, and the quality of the bottle is 112.5 grams after filling. Then the volume of this perfume bottle is Cubic centimeter
4. When a beaker is filled with water, the total mass is 350 g. when an alloy metal block is put in, some water overflows. This is the total mass of 500 g. when the alloy block is taken out, the total mass is 300 g, then the alloy density is 100 g________ Kg / m3

1.A
2.C
three point five zero
four point four

For three hollow metal spheres made of copper, iron and aluminum with the same mass and volume, the largest volume of the hollow part of the three spheres is & nbsp; (ρ copper > ρ iron > ρ aluminum) ()
A. The volume of the hollow part of the copper ball is the largest B. the volume of the hollow part of the iron ball is the largest C. the volume of the hollow part of the aluminum ball is the largest D. the volume of the hollow part is the same

∵ ρ = MV, ρ copper ∵ ρ iron ∵ ρ aluminum, the three balls have the same mass, ∵ the volume of copper is the smallest, ∵ the volume of the three balls is the same, V space = V ball-v, ∵ the hollow part of copper ball is the largest, and the hollow part of aluminum ball is the smallest

The density of Science in grade eight
(in order to determine the density of a metal block, Xiao Zhang designed a simple experiment. Fill a glass with water and weigh the total mass to 380g. After the metal is put in, some water overflows, but the water is still full. Weigh the total mass to 516g. Then take the metal block out of the glass carefully, The total mass of the glass and the remaining water is 360g. Then he claimed that the density of the metal block has been calculated. I know the process of calculating the density of the metal block from the experimental data provided above, but there is a step that I can't understand. 380-360 = 20 (the mass of water with the same volume as the metal). Isn't the water on the metal? How can it be the same volume as the metal

The volume of 20g water is the same as that of metal, because the water is full, and the volume of overflow is the volume of metal
The density of water can be used to calculate the volume of metal (water)
516-360 = weight of metal. If you know the weight and volume of metal, you will know the density of metal

Density of water in eighth grade science exercise book B 3
RT
It's due tomorrow,

1. Mass volume P = m / V 2. Capacity 3.77.4g 30ml 2.5g/cm 34.c5.7006. (1) bacd (2) 18 8 2.57. (1) v = m / P = 1000kg / 1000kg m3 = 1 (M3) = 1000L n = 1000L / 5L times = 200 times (2) V ^ = 9l-5l = 4L v = 4L * 10 * 30 = 1200L = 1.2 (M3) M = PV = 1000kg / m3 * 1.2m3 = 1200kg

The mass ratio of solid body a and solid body B is 2:1, and the density ratio of solid body a and solid body B is ()
A. 2:1b. 1:2c. 1:1d. Unable to judge

Because it is a solid body of the same material, the density is the same, that is, the ratio of density is 1:1

What are the forms of water in nature? Under what conditions can they be transformed into each other?

Problem 1. Three forms of water: ice (solid) water (liquid) steam (gas)
Problem 2: ice can melt into water, water can evaporate into steam, steam can condense into water, and water can freeze into ice
Drawing: draw a piece of ice, draw a sun on it, and then draw an arrow under the ice, draw water (and so on, water can evaporate into steam)
In the second half of the sentence, you use some air to express it, and then make an arrow at the back - air conditioner