When measuring the density of a small solid object, a physics interest group adopted the following experimental operations: first, the mass mo of the object was measured with a balance; then, a certain amount of water was put into a small beaker, and the total mass M1 of the beaker and water was measured with a balance; then, after the object was tied up with a thin line, the mass M1 of the beaker and water was measured, The object is immersed in the water of the beaker (the water does not overflow and the object does not touch the beaker) by holding a thin line in hand. At this time, the measured value of the balance is m2, as shown in Figure 6 A. The buoyancy of an object in water is MOG B. The buoyancy of an object in water is (m2-ml) g C. The density of the object is Mo / m2-m1 * P water D. The density of the object is Mo / m2-m0 * P water 、 I don't understand at all. I'm going to take the senior high school entrance examination right away. It's really disturbing that I don't understand

Ninth grade pressure and buoyancy work and mechanical energy and thermal energy formula and explanation

Pressure:
Pressure = pressure / stressed area
P=F/S
Because the definition of pressure is the effect of pressure
The effect of pressure is related to pressure and area
The greater the pressure, the greater the pressure
When the pressure is constant, the smaller the stress area is, the greater the pressure is
So pressure = the ratio of pressure to the area under force
Liquid pressure:
P = liquid density * g * h
deduction:
P = f / S = g liquid / S = m liquid * g / S = liquid density * V * g / S = liquid density * h * s * g / S = liquid density * g * h
Buoyancy:
F = liquid density * g * V row
deduction:
F floating = g row = m liquid * g = liquid density * g * V row
I don't understand "work and mechanical energy, heat and energy"
Work and mechanical energy?
Mechanical energy is the general name of kinetic energy and potential energy
The more mechanical energy you have, the more work you can do
The stronger the ability of an object to do work
Heat and energy

Buoyancy, all the formulas for work
Including deformation formula

Velocity: V (M / s) v = s: distance / T: time gravity: G (n) g = Mg (M: mass; G: 9.8N / kg or 10N / kg) density: ρ (kg / m3) ρ = m / V (M: mass; V: Volume) resultant force: fhe (n) same direction: fhe = F1 + F2; opposite direction: fhe = F1-F2, opposite direction, F1 > F2 buoyancy: FFU (n) FFU = g object-g view (gsight: gravity of object in liquid) ）Buoyancy: F floating (n) f floating = g object (this formula only applies to floating or suspending objects) buoyancy: F floating (n) f floating = g row = m row, g = ρ liquid GV row (g row: gravity of the liquid; m row: mass of the liquid; ρ liquid: density of the liquid; V row: volume of the liquid (i.e. volume immersed in the liquid)) balance condition of lever: f1l1 = f2l2 (F1: power) L1: power arm; F2: resistance; L2: resistance arm) fixed pulley: F = g object s = H (F: the tension on the free end of the rope; G object: the gravity of the object; s: the moving distance of the free end of the rope; H: the lifting distance of the object) movable pulley: F = (g object + G wheel) / 2 s = 2 h (g object: the gravity of the object; G wheel: the gravity of the movable pulley) pulley block: F = (g object + G wheel) s = n h Mechanical work: w (J) w = fs (F: force; s: moving distance in the direction of force) active work: w you = g object h total work: W total w total = FS when pulley block is placed vertically mechanical efficiency: η = w you / W total × 100% power: P (W) P = w / T (W: work; t: time) pressure P (PA) P = f / S (F: pressure; t: time) pressure; S: Force area) liquid pressure: P (PA) P = ρ GH (ρ: density of liquid; H: depth [vertical distance from liquid surface to required point]) heat: Q (J) q = cm △ t (C: specific heat capacity of material; m: mass; △ T: temperature change value) heat released by fuel combustion: Q (J) q = MQ (M: mass; Q: calorific value)

What is Bernoulli equation?

Bernoulli equation is set in the thin tube in the right figure. There is a steady flow of ideal fluid, and the flow direction is from left to right. We cut a section of fluid at A1 and A2, that is, the fluid between A1 and A2, as the research object. Let the cross-sectional area of A1 be S1, the flow velocity be V1, and the height be H1

What is the physical meaning of Bernoulli equation?

1、 Under general conditions, the significance of Bernoulli's equation in terms of P + 1 / 2 ρ V2 + ρ GH = constant. The equation shows that when an ideal fluid flows stably in a flow tube, the sum of kinetic energy 1 / 2 ρ V2 per unit volume, gravitational potential energy ρ GH and pressure P at the point is a constant

What is the physical meaning of Bernoulli equation for real liquid?

That is, the loss of system energy caused by the resistance of liquid viscosity is considered, so that the system energy is conserved

The element of water velocity should be included in the calculation formula

Is it Bernoulli equation: P + ρ GZ + (1 / 2) * ρ V ^ 2 = C
Where p, ρ and V are the pressure, density and velocity of fluid respectively; Z is the vertical height; G is the acceleration of gravity; C is a constant

What are the continuity theorem and Bernoulli equation of fluid? What are their physical meanings

2. Formula: s1v1 = s2v2, where: S1, V1 are the area of flow section 1 (M & # 178;) and velocity (M & # 179 / s); S2, V2 are the area of flow section 2 (M & # 178;) and velocity (M & # 17;)

What is the physical meaning of continuity equation, Bernoulli equation and momentum equation
As long as the physical meaning

Continuity equation is the concrete expression form of mass conservation law in fluid mechanics
Bernoulli equation is the dynamic equation of steady flow of ideal fluid, which means that the sum of pressure potential energy, kinetic energy and potential energy of any two points on the streamline remains unchanged when the viscous loss is ignored
Momentum equation is the expression of momentum conservation law in fluid mechanics

What is the physical quantity of velocity and what is it equal to?

Speed is a physical quantity that represents the speed of an object's motion. It is equal to the displacement divided by the time needed to pass through the displacement, v = x / T
However, to accurately express the speed of motion, we need to compare its instantaneous speed, that is, the time is very small, approaching 0