Physical pressure calculation questions for junior high school students! It s very urgent

Child = mg s = (40kg*10n kg) [Because the pressure of one foot of a child is stronger than the bearing capacity of the ice surface, it is not possible.]

2.⑴g=pvg=

The minimum force area of the iron block on the ground s=

The maximum pressure of the iron block against the ground p=f s=78n 3Because the pressure and gravity are in the same direction, f = g, according to p = f s, g total = p * s = 1800 pa * (5 * 10 -12) = 90ng object = g total -g container = 90n - 15n = 75n f = pghs = 1000kg m 3 * 3m * 10n kg * (3m * 3m) = 40000 pa * 9m = 360000n

The lowercase p is density, the uppercase p is pressure, and this symbol represents the power.

1) Iron block volume v=

Iron mass m= v=

The pressure of the iron block on the ground is equal to the gravitational force f=g=mg=

2) The minimum force area of the iron block on the ground s=

The maximum pressure of the iron block on the ground p=f s=78n because the pressure and gravity are in the same direction, f=g, according to p=f s.

g total = p * s = 1800 pa * (5 * 10 -12) = 90ng object = g total - g container = 90n - 15n = 75n

A 300 cm3 bottle contains 200 cm3 of water, and a thirsty crow throws a pebble with a mass of 12 grams into the bottle at a time, and when the crow throws 25 identical pebbles, the water rises to the mouth of the bottle. (g takes 10 N kg).

Find: (1) What is the total volume of the stones in the bottle?

2) What is the density of the stones?

3) How buoyant is each stone in the water?

4) If the contact area between the bottom of the bottle and the ground is 50cm2, how much pressure does the bottle have on the ground when the water surface rises to the mouth of the bottle? (Bottle mass is not counted).

It is equal to the pressure divided by the area of action.

I looked at it - I didn't write it carefully, I just knew that the mass was kg, that is.

The following calculations, alcohol is taken , g is taken.

Because "the pressure at points A and B at the bottom meter of the two containers is 980 Pa", it can be seen that the depth of water = and the depth of alcohol = in the above. So what are the conditions for starting the depth of water and alcohol in the container? The answer is the depth of water = and the depth of alcohol =.

If water and alcohol are pumped at the same depth, so that the pressure of water and alcohol on the bottom of the two containers A and B is equal, of course, the depth of each should be extracted, so the same volume of extraction = cubic meters, mass: water 3kg, alcohol.

Start the depth of the water as.

Start with a depth of alcohol.

Pumping cubic meters of liquid in the same volume.

Suppose the depth of the extraction is h water g (wine g ( H=

This should be based on the pressure formula water multiplied by g times the height of A = alcohol multiplied by g times the height of B, because the height is equal, so as long as the density of alcohol is equal to the density of water!

The magnitude of buoyancy is equal to the weight of the overflowing water f buoyancy = g row = mg

The block is floating in the water, the lower part of the block is immersed in the water, and the upper part is exposed to the water. According to the buoyancy force equal to the difference between the upper and lower pressure of the liquid on the object, the buoyancy force is the pressure of the water on the lower surface of the wooden socks or socks, and the pressure is f=6n.

The pressure of water on the lower surface of the block p=f s=6n (

The pressure difference crack grinding type is the weight of the beam pressure limiting valve divided by the area of the outlet = 100g*10 (-3)*pie*(

PA15258PA atmospheric pressure.

At least how much force can be withstood at the interface between the lid and the pot?

Pressure Guess Difference * Pot Area = 15258 * Pie * (

Cattle. Note: Indicates to the power of the power.

There are many ways to do this, but you said it was a pressure topic in the third year of junior high school.

That is, to increase the pressure, and the higher the pressure, the higher the boiling point.

Answer: 1. The pressure handle is made wide to reduce the pressure.

2. Two erasers are padded at the bottom to increase the friction between the stapler and the desktop.

3. The staple (needle edge) is very sharp and thin, which is conducive to increasing the pressure.

4. The base is made wide to reduce the pressure.

1. Seek pressure: An object is a cube, 10cm wide and 1cm thick, and it is full of water. Throw it into 100m deep water during a voyage to find the pressure on each surface of the cube.

2. Find the pressure: there is a smooth inclined plane with a slope of 30 degrees high by 1m, and a small object rushes from the bottom of the inclined plane to the inclined plane at a speed of 10m in less than a second, and asks the pressure of the object on the inclined plane when it reaches the center height. 3. Solubility: Yes.

A glass of liquid 500g, it is unknown that it can be jealous, the existing 100g of table salt, put it into the liquid to completely dissolve, weigh 506g Q, the solubility of the liquid is.

How much. 4：