2.( 1)a, pressure, all directions

Equal depth

density

(2) p = height, depth and density

(2)

1, open, connected

2, the same liquid, when not flowing.

3. Lock

Second,

Example 1, b

Example 2, 1: 1, 1: 3.

Example 3, a

In Example 4, (1) density was increased.

(2) Liquid density, depth and probe direction

(3)300,280

The rubber diaphragm of the pressure gauge shares part of the pressure.

Third, classroom exercises.

1、C、A

2、200000,4000

3. The deeper the liquid, the smaller the stress area.

4.ACD(D is worth considering)

5.( 1) pressure gauge

(2) In the same liquid at the same depth

6. A.

7、C

8、C

9、B

Fourth, extracurricular expansion.

10 、( 1)P =ρGH = 1000× 10×0. 12 = 1200

(2)f=ps= 1200×4× 10^-3=4.8n

P = f/s = gtotal /s = (0.4+0.6) g/0.004 = 2500 pa.

1 1, lower volume: V 1= 1000cm3.

1 100g The total volume of water is: v =1100/0 =100cm3.

Therefore, the volume of the upper water v' =1100-1000 =100cm3.

Namely: Sh= 100, h= 100/25=4cm.

So the whole water depth: 10+4 = 14cm.

p =ρGH = 10000×0. 14 = 1400 pa

f=ps= 1400× 100× 10^-4= 14n

4D 3B 1A，2C，5B，6BD，7C

8, unchanged, bigger

9、5:4,4:5

10, greater than b

1 1、4N， 1000pa

12, smaller, bigger, unchanged, bigger

13、=,=

14、P=ρhg

5000=ρg×0.5

ρ= 1000 kg/m3

G water = rho water VG =1000× 0.002×10 = 20n.

P=G total /s = (20+20)/0.002 = 20000 pa.

15、P=ρgh

9000000=900× 10×h

H =1000m

1000-800 = 200m

Can run 200 meters

f = PS =ρGHS = 900× 10×200×3. 14×0. 1×0. 1 = 56520n

The above answers are for reference only. In a hurry, mistakes are inevitable. For detailed answers, please leave a message and ask questions.