Calculations

Basic Mechanical Calculations

  • Understand the calculation of work, which is a product of force and distance. Remember that work is measured in joules (J) in the metric system.
  • Explain the concept of power, which is work done per unit of time. Power is measured in watts (W), where one watt equals one joule per second.
  • Determine the mechanical advantage of a system, which is the ratio of output force to input force. This measure is essential in evaluating the effectiveness of a mechanical system.
  • Calculate velocity ratios, which is the ratio of the input speed to the output speed in a mechanical system.

Pressure in Pneumatic Systems

  • Explain the equation for pressure which is force divided by area. Pressure is measured in pascals (Pa), with one pascal equal to one newton per square metre.
  • Calculate volume using appropriate formulae depending upon the shape of the vessel containing the pneumatics.
  • Understand how to determine the mass of a given volume of gas at a given pressure, using the ideal gas law: PV = mRT, where P is pressure, V is volume, m is mass, R is the specific gas constant, and T is absolute temperature.

Forces and Torques in Mechanical Systems

  • Calculate the force exerted by a mechanical system using the formula F=ma, where F is the force, m is the mass, and a is the acceleration.
  • Determine the torque in mechanical systems, which is the product of force and distance from the pivot point. Torque is measured in newton-metres (Nm).

Energy in Mechanical and Pneumatic Systems

  • Understand the relationship between kinetic energy, mass and velocity with the formula: KE = 0.5mv².
  • Explain how potential energy is calculated as potential energy = mass x gravity x height.
  • Calculate the energy within a pneumatic system using the formula E=PV, where E is energy, P is pressure, and V is the volume of the gas.

Fluid Flow in Pneumatic Systems

  • Understand and calculate the flow rate of a fluid (Q), which is the volume of fluid passing through an area per unit time.
  • Differentiate between laminar and turbulent flows. Laminar flow is smooth and orderly, while turbulent flow is chaotic and irregular.
  • Identify and calculate Reynolds number, a dimensionless quantity used to predict fluid flow patterns.