Units
Pressure – Bar
Energy / Work – Joule
Power – Watt
Farad is the unit of capacitance
Henry is the unit of inductance
Coulomb is the unit of Electric charge
The SI unit of electrical resistance is the ohm (Ω)
Siemens is the unit of Electrical resistance and conductance
The maximum frictional force, when a body just begins to slide is called Limiting friction
Factor of safety
The ratio of ultimate stress to the working stress
Poisson's ratio
The ratio of Lateral strain to linear strain
Bulk modulus
The ratio between direct stress and volumetric strain
Modulus of Rigidity
The ratio of shear stress to the displacement per unit sample length (shear strain)
Young’s modulus
Young’s modulus (Y) is the ratio of the tensile/compressive stress (σ) to the longitudinal strain (ε).
✓ Compressive stress is formed when the section is subjected to axial pushes
✓ A cantilever beam having uniformly distributed load on the entire length, then the maximum bending moment will be at the fixed end
When one of the links of a kinematic chain is fixed, then the chain is called mechanism
Radiation is the process of heat transfer from hot body to cold body without effecting the medium.
Conduction is the process by which heat or electricity is directly transmitted through the material of a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material.
Convection is the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.
Density is the mass per unit volume.
Velocity = Displacement/Time (V=D/t)
Pressure at a point is the force per unit area
Momentum of a body is given by Mass x Velocity
Pascal's law
Pressure at a point in a fluid is equal in all directions
Planck's law
Planck's law describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given
temperature (T), when there is no net flow of matter or energy between the body and its environment.
Bernoulli's principle
Bernoulli's principle states that an increase in the speed of a fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy.
Working of orifice meter is based on Bernoulli's theorem
A sprayer make use of Bernoulli's theorem
Archimedes' principle
Archimedes' principle the buoyant force is equal to the weight of the displaced water
Pressure – Bar
Energy / Work – Joule
Power – Watt
Siemens is the unit of Electrical resistance and conductance
The maximum frictional force, when a body just begins to slide is called Limiting friction
Factor of safety
The ratio of ultimate stress to the working stress
Poisson's ratio
The ratio of Lateral strain to linear strain
Bulk modulus
The ratio between direct stress and volumetric strain
Modulus of Rigidity
The ratio of shear stress to the displacement per unit sample length (shear strain)
Young’s modulus
Young’s modulus (Y) is the ratio of the tensile/compressive stress (σ) to the longitudinal strain (ε).
✓ Compressive stress is formed when the section is subjected to axial pushes
| Material | Young’s modulus | Elastic Limit | Tensile Strength |
| Y (10^9 N/m²) | (10^7 N/m²) | (10^7 N/m²) | |
| Aluminum | 70 | 18 | 20 |
| Copper | 120 | 20 | 40 |
| Wrought Iron | 190 | 17 | 33 |
| Steel | 200 | 30 | 50 |
| Bone | |||
| Tensile | 16 | 12 | |
| Compressive | 9 | 12 | |
Radiation is the process of heat transfer from hot body to cold body without effecting the medium.Conduction is the process by which heat or electricity is directly transmitted through the material of a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material.Convection is the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.
Density is the mass per unit volume.
Relative density, or specific gravity, is the ratio of the density of a substance to the density of a given reference material.
Velocity = Displacement/Time (V=D/t)
Velocity is a vector expression of the displacement that an object or particle undergoes with respect to time (m/s)
Weight is the measure of the intensity of the force imposed on the object by the local gravitational field.
Mass is a measure of the amount of matter in an object.
Specific weight (also known as the unit weight) is the weight per unit volume of a material.
Specific volume is defined as the volume per unit mass.
Pressure at a point is the force per unit area
The viscosity of a fluid is a measure of its resistance to deformation at a given rate.
Momentum of a body is given by Mass x Velocity
1 Metric horse power = 736 watts
1 Mechanical horse power = 746 watts
Hooke’s law
Hooke’s law states that for material loaded within elastic limits, the stress is proportional to strain, produced by stress.
Fleming's law
Pascal's law
Pressure at a point in a fluid is equal in all directionsPlanck's law
temperature (T), when there is no net flow of matter or energy between the body and its environment.
Bernoulli's principle
Bernoulli's principle states that an increase in the speed of a fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy.
A sprayer make use of Bernoulli's theoremArchimedes' principle
