Govt. Exams
Entrance Exams
Deep groove ball bearings are ideal for high-speed applications with moderate radial and axial loads due to their low friction and good precision.
Module is defined as the ratio of pitch circle diameter to the number of teeth (m = D/N). It determines the size of the gear teeth.
A key is a mechanical element that prevents relative rotational motion between a shaft and a hub or pulley by transmitting torque.
U₂ = π × 0.3 × 1500/60 = 23.56 m/s. This velocity is critical in pump design as it affects the Euler's head and pump efficiency in Indian water supply and irrigation projects.
In Bernoulli's equation (P/ρg + V²/2g + Z = constant), when flow is in a horizontal pipe at constant elevation, Z (potential energy head) remains constant and can be neglected in differential form.
Using continuity equation: A₁V₁ = A₂V₂. Area ratio = (D₁/D₂)² = (100/50)² = 4. Therefore V₂/V₁ = 4:1. This is critical for pipe flow analysis in water supply systems.
Pascal's law states that pressure applied to a confined fluid is transmitted undiminished in all directions. This principle is fundamental to hydraulic systems used in Indian industries.
Mach number classification: M < 1 (subsonic), M = 1 (sonic), 1 < M < 5 (supersonic), M > 5 (hypersonic). M = 1.2 is supersonic.
In a convergent nozzle, pressure decreases and velocity increases due to Bernoulli's principle. Temperature may decrease due to pressure drop.
Hagen-Poiseuille equation applies only to laminar flow where Re < 2300. Beyond this critical value, flow becomes transitional or turbulent.
