There are 50 physics calculation questions, and 60 physics calculation questions

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Summary. Hello, classmate, send your question.

Hello, classmate, send your question. Ok good.

Is this a problem for you?

You can show me your full title, because you can't seem to find it this way, so I'll write it for you.

How did you get that niu?

I'm sorry it's a bit messy, and I can't read it.

I just didn't see it.

Now I'm writing it for you.

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That's right. Just bring it in and solve.

Because he has a U-party.

If you have any questions, you can ask me, I also wrote about this topic in my senior year of high school before.

1.When a submarine is sailing on the surface of the sea, the displacement is 4000 tons, and when it sucks in 2000 tons of seawater, it can dive underwater, so what is the volume of the submarine exposed when it is sailing on the surface? What is the volume immersed in water?

How much does a submarine weigh? (g=10n/kg)

2.If a heavy object floats on a liquid surface, with a volume of 25cm3 exposed, if the vertical downward pressure is applied to the object, the object is just immersed in the liquid, what is the density of the liquid and the object? (g=10n/kg)

3.If there are two pieces of iron and aluminum of the same volume submerged in water, if the buoyancy of the iron block in the water is known, and the weight of the aluminum block is 135n, find: (1) the buoyancy of the aluminum block in the mixed water.

2) The density of the aluminum block (g=10n kg).

The equivalent density of Qi iron in the water cave is 6800kg m3, then the volume of iron is one unit (the unit of your spring dynamometer is not sold, I default to Newton), then Naling is 15600kg in the air

One. The speed of the motorcycle is 40 meters per second, and it takes 340 40 = seconds to run to the line of this person, at this time, Li Chengzhen entered the meter before the pedestrian, and there are meters away from the road, so the person can pass safely at the original rough speed.

When the person heard the sound of the motorcycle starting, one second had passed (the speed of sound was 340 meters per second), so the motorcycle was 340-40 = 300 meters away from the person.

The above analysis does not take into account the acceleration process of the motorcycle.

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Solution: The density of water is 1000kg m3, that is, 1g cm3, which can be known according to the principle of Kiakimedean buoyancy;

The mass of the wood block immersed in water is: 1g cm3 * 60cm3 = 60g The volume immersed in water accounts for 60cm3 (60cm3 + 40cm3) = 3 5

So the weight of the wooden block is 60g 3 5 = 100g

A: The buoyancy experienced by the wooden block is 60g, and the mass of the wooden block is 100g.

Buoyancy = Wood block gravity = mass * 10 = volume * density * 10 density you check for yourself.

f(float) = (air) vg=

n (number of people) = [f (floating) - f (self-weight)] f (weight of people) = 5

The number of people is an integer, it cannot be a decimal, and it cannot be rounded, and if it is large, it will not be able to fly.

The sound travels faster in steel, and the second sound travels through the air, which should be 2 seconds.

The time it travels inside the steel t=

v=680/