Mechanical Properties of Fluids — Class 12 Maharashtra HSC Physics revision notes
A 7-page visual revision sheet for Mechanical Properties of Fluids, written for Class 12 Maharashtra HSC Physics. Formulas, diagrams and the traps that cost marks, laid out to be read the night before rather than the term before. Free, and it opens inside CapCompass.
Page 1 as PDF
Mechanical Properties of Fluids in one look
pressure, skin, drag and the price of going faster
What counts as a fluid
- anything that can flow: liquids, gases and plasmas
- a fluid has zero shear modulus, so it cannot resist shearing at all
- an ideal fluid is incompressible, irrotational, nonviscous and in steady flow
Pressure
- definition
P = F/A - due to a liquid column
p = hρ g - absolute pressure at depth h
p = p_0+hρ g - gauge pressure
p - p_0 = hρ g - SI unit and dimensions
Pa = N/m^2, [L^-1M^1T^-2]
What the column formula says
- p=hρ g has no area or shape term: pressure depends only on depth
- the hydrostatic paradox: connected vessels of any shape have liquid at the same level
- resolution: sloping walls push back with a vertical component, carrying the extra weight
- Pascal's law: extra pressure on an enclosed fluid goes undiminished everywhere
Measuring pressure
- mercury barometer: inverted tube in a trough, Torricelli's vacuum above the column
- p_0=hρ g: one atmosphere is 76 cm mercury = 760 torr
- open tube manometer: one limb open to air, height difference gives gauge pressure p-p_0
- mercury is dense, keeping the column short, but is hazardous, no longer used in schools
Page 1 of 7. The full sheet, all 7 pages, opens free in the app.
What this Mechanical Properties of Fluids sheet covers
- What counts as a fluid
- pressure
- definition
- due to a liquid column
- absolute pressure at depth h
- gauge pressure
- SI unit and dimensions
- Depth, shape, piston
- What the column formula says
- Measuring pressure
- Barometer, manometer, gauge
- Lift and brake
- surface tension
- Surface tension, the molecular picture
- Surface tension and surface energy
- work to make new surface
- force on a film with two surfaces
- water at 20 ° C
- mercury at 20 ° C
- Molecules, film, energy
- What changes surface tension
- Impurity
- Temperature
- Angle of contact
- Excess pressure in a drop and a bubble
- liquid drop, one surface
- soap bubble, two surfaces
- air bubble inside a liquid
- Water, mercury, detergent
- Drop, bubble, joined bubbles
- capillarity
- capillary rise
- Capillary action
- radius of the meniscus
- rise or fall
- surface tension from a rise
- weight of the raised column
- upward pull of the surface
- Streamline flow and turbulent flow
- Streamline, or laminar
- Turbulent
- Rise, fall, radius
- Streamlines, continuity, turbulence
- continuity
- Equation of continuity
- mass in equals mass out
- so for an incompressible fluid
- in one line
- Critical velocity and Reynolds number
- critical velocity
- Reynolds number
- Reading the Reynolds number
- viscosity
- coefficient of viscosity
- Layers, pipe, temperature
- Temperature pulls the two phases opposite ways
- Stokes law
- terminal velocity
- Stokes' law and terminal velocity
- viscous force on a small sphere
- at terminal velocity
- so the coefficient of viscosity
- Falling ball
- Weighing and floating
- Bernoulli
- Bernoulli's equation
- the full statement
- rearranged
- Pipe, Venturi meter, Torricelli
- Lift on a wing and a spinning ball
- Units and dimensions
- P pressure
- T surface tension
- η coefficient of viscosity
- ρ density
- R_n Reynolds number
- Traps that cost marks
- Tricks that save time
How CapCompass uses this sheet
These notes are not a standalone PDF. CapCompass plans Physics chapter by chapter against your real exam dates and free hours, and when the plan reaches Mechanical Properties of Fluids the sheet opens inside the study block itself — at the page covering the sub-topic that block is on, with the timer still running. Revision arrives at the moment the plan says revise, instead of having to be gone looking for.
More Physics Class 12 revision notes
- AC Circuits
- Current Electricity
- Dual Nature of Radiation and Matter
- Electromagnetic Induction
- Electrostatics
- Kinetic Theory of Gases and Radiation
- Magnetic Fields due to Electric Current
- Magnetic Materials
- Oscillations
- Rotational Dynamics
- Semiconductor Devices
- Structure of Atoms and Nuclei
- Superposition of Waves
- Thermodynamics
- Wave Optics