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Types of mechanical forces

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A force exerted on a body can cause a change in either the shape or the motion of the body.The unit of force in SI system is the Newton(N) and CGS system is dyne.No solid body is perfectly rigid and when force are applied to it,changes in dimension occur.such changes are not always perceptible to the human eye since they are negligible. For the example,The span of a bridge will sag under the weight of a vehicle and a spanner will bend slightly when tightening a nut. It is also important for civil engineers and designers to appreciate the effects of forces on materials.Together with their mechanical properties of the materials. There three main types of mechanical forces that can act on a body.They are 1)Tensile force 2) compressive force and 3) shear force
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What is venturimeter?

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A venturimeter is a device used for measuring the rate of a flow of a fluid flowing through a pipe.
It consists of three parts.
  1.  A short converging part
  2.  Throat
  3.  Diverging part
It is based on the principle of Bernoulli’s equation. Inside of the venturimeter pressure difference is created by reducing the cross-sectional area of the flow passage. The pressure difference is measured by using a differential U-tube manometer. This pressure difference helps in the determination of rate of flow of fluid or discharge through the pipe line. As the inlet area of the venturi is large than at the throat, the velocity at the throat increases resulting in decrease of pressure. By this, a pressure difference is created between the inlet and the throat of the venturi.
venturimeter
Let
D1 and D2  —  Diameter at inlet and throat respectively
P1and P2    —  Pressure at inlet and throat
V1 and V2  — Velocity at inlet ad throat

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