Under what conditions is f floating = ρ liquid GV discharged, under what conditions is f floating = g discharged, f floating = m discharged, G discharged

Under what conditions is f floating = ρ liquid GV discharged, under what conditions is f floating = g discharged, f floating = m discharged, G discharged

Suspension of the whole body in the liquid, V row is equal to the volume of the body, f floating = g row
Floating part of the object in the liquid, V row is equal to the volume of the submerged object, f floating = ρ liquid GV row
Precipitation of the whole body in liquid, V row is equal to the volume of the body, f floating = m row, G
The formula of liquid pressure is p = ρ, liquid GH, and pressure P = f / s. here s is the liquid pressure, which is the gravity of the object carried by the hydraulic pressure
1 suspension: when the object is suspended in liquid, only the hydraulic pressure on the lower surface, that is, the pressure is p = ρ, liquid GH, and P = f / s. h is the depth of the object under the liquid level
So f / S = ρ liquid GH, that is, f = ρ liquid GH * s, h * s = V is the volume. This volume V is the volume of the object immersed in the liquid, that is, V row
Floating: same as the principle of hydraulic pressure difference above
The sum of the hydraulic pressure on the side of the object is still 0. At this time, the hydraulic pressure has two parts: the hydraulic pressure on the upper surface and the hydraulic pressure on the lower surface
The upper surface is P1 = ρ liquid g * (H1), and the lower surface is P2 = ρ liquid g * (H2)
The difference of hydraulic pressure is p2-p1 = ρ g * (h2-h1), where h2-h1 is the height of the object
Because P = f / s, the resultant force F = ρ liquid g * (h2-h1) * s, (h2-h1) * s = V is the volume of the object, that is, the volume completely immersed in the liquid
Precipitation: in fact, like floating, buoyancy is only determined by liquid density, row g and V, which has nothing to do with the position of the object in the liquid. Therefore, like suspension and precipitation, the pressure difference is equal, because the pressure difference p2-p1 = ρ liquid g * (h2-h1), the same object (h2-h1) is constant, that is, the height of the object is constant

1. When an egg with a mass of 50g is suspended in brine, its buoyancy is () n. [g = 10N / kg]
2. When a ship with a displacement of 1000t sails in the river, the total weight of the ship and its cargo is () n when it is fully loaded, and the buoyancy of the river is () n. if the density of the river is 1.0 times the third power of 10 kggm3, the volume of the River discharged by the ship is () m3. [take g = 10N / kg]
3. When a ship sails into a river from the sea, the gravity it receives, the buoyancy it receives, and the volume of water it discharges
4. The mass of boiled water discharged by a ship is 2600t when it is empty and 5800t when it is full. Q: what is the mass of the ship itself? How much cargo can it carry at most?

1. Because of suspension, f = g = m · g = 0.05kg * 10N / kg = 0.5N
2. Because of full load, displacement = total mass of ship and cargo, gtotal = m displacement · g = 1000000kg * 10N / kg = 10000000n
3. Because it is always near the earth, G is constant, because the mass m is constant, G is constant according to g = m · g. because it is always floating, f is floating = g, because G is constant, f is floating. According to Archimedes principle, f is floating = g, so the gravity of discharged water is constant, because G is constant, according to g = m · g, M is constant, because the density of river water is less than that of sea water, according to ρ = m / V, M is constant, so V River > V sea, So the volume of boiled water becomes smaller
4. ∵ floating, f floating = g ship, according to Archimedes principle, f floating = g row ∵ g row = g ship, ∵ g = m · g ∵ m ship = m row = 2600t
According to Archimedes' principle, f-floating '= g row'; g-total = g row '; g = m · G'; m-total = m row '= 5800t, ∵ m-total = m ship + m cargo, ∵ m cargo = m-total-m ship = 5800t-2600t = 3200t

An apple with a mass of 0.2N floats in a cylindrical container filled with water, and the bottom area of the container is 100 square centimeters

The buoyancy of a floating object is equal to its own gravity, which has nothing to do with the shape of the container, i.e. 0.2N

For example, when a ship sails into the Yangtze River from the sea, its buoyancy (rising, sinking, unchanged) changes (increasing, decreasing, unchanged) and other changes, etc

Answer: sink (not sink, sink a little, still float) and remain unchanged
Analysis:
Ship is floating, buoyancy is equal to gravity, gravity does not change, so buoyancy does not change
But the density of sea water is large: F floating = ρ liquid GV discharge, when the buoyancy is fixed, ρ liquid is large, V discharge is small; the density of sea water is large, so the volume of discharge is small
Similarly, if a submarine sails from fresh water to sea water under the water surface, at that time, because the V 'row remains unchanged, the ρ liquid is large and the buoyancy is large

What are the five ways to find buoyancy?

There are four main methods. 1. Buoyancy is equal to the pressure difference between the upper and lower surfaces, f floating = f lower - f upper
2. Weighing method is generally used to put the object to sink in the water. The gravity in the air minus the pulling force in the water. F float = g - f pull
3. Archimedes principle f floating = g row = ρ VG is mainly used to calculate buoyancy when objects are completely submerged
4. Sinking and floating conditions, mainly used to calculate the floating or floating objects when f floating = g objects

The concept of the law of conservation of mechanical energy?
Hope someone can answer me!

Only the kinetic energy of gravity and potential energy can be transformed into each other in the mechanical system
However, the conservation of mechanical energy is caused by the following conditions: 1) only subject to gravity or elastic force; 2) except gravity or elastic force, the resultant force of other forces is 0; 3) except gravity and elastic force, other forces do no work; 4) except gravity and elastic force, the work of other forces is 0

F = ma, where M = 8, a = 10

If the unit of known condition is the main unit of international system of units, that is, M = 8kg, a = 10m / S ^ 2
Then f = ma = 8 * 10 = 80N

What are the seven basic physical quantities and what are their units

The seven basic physical quantities are: length (m), time (s), mass (kg), current intensity (a), thermodynamic temperature (Kelvin K), quantity of matter (mol), luminous intensity (candela CD). In brackets are their units in the international system of units

What is the physical quantity of the lithium battery used on the mobile phone marked with "3.6V 900mA · H"?

3.6V is the rated voltage of the battery, which is 3.6V
900mAh is the capacity of the battery. The unit is MAH. It means that if you discharge with 100mA current, you can discharge for 9 hours; if you discharge with 450mA current, you can discharge for 2 hours and so on

The lithium batteries used on mobile phones are marked with "3.6V & nbsp; & nbsp; & nbsp; 900mAh", where MAH is the physical quantity______ The average working current of the mobile phone is______ Ma, the mobile phone battery can store electric energy of______ J．

Mah is the unit of charge quantity, 900mAh = 3240c; once charged, it can be used for 3 days. The average working current of the mobile phone is I = QT = 900mAh, 3 × 24h = 12.5ma, and the electric energy that the mobile phone battery can store is w = UQ = 3.6V × 3240c = 11664j