static

Examples of static in the following topics:

• Friction: Static

  • Another type of frictional force is static friction, otherwise known as stiction.
  • Unlike kinetic friction, however, static friction acts to resist the start of motion.
  • Static friction originates from multiple sources.
  • Putting these elements together gives the maximum force of static friction as:
  • In general, the force of static friction can be represented as:

• Static Equilibrium

  • Any region or point, or any static object within a static fluid is in static equilibrium where all forces and torques are equal to zero.
  • Static equilibrium is a particular state of a physical system.
  • The analysis and study of objects in static equilibrium and the forces and torques acting on them is called statics—a subtopic of mechanics.
  • Statics is particularly important in the design of static and load bearing structures.
  • As it pertains to fluidics, static equilibrium concerns the forces acting on a static object within a fluid medium.

• Pascal's Principle

  • Pascal's Principle states that pressure is transmitted and undiminished in a closed static fluid.
  • Pascal's Principle (or Pascal's Law) applies to static fluids and takes advantage of the height dependency of pressure in static fluids.
  • As a result of Pascal's Law, the pressure change (pressure applied to the static liquid) is transmitted undiminished in the static liquid so that the applied pressure is 2 N/m2 at the bottom of the bottle as well.
  • By Pascal's Principle, P1 = P2, yielding a force exerted by the static fluid of F2, where F2 > F1.
  • Two different types of hydraulic press configurations, the first in which there is no difference in height of the static liquid and the second in which there is a difference in height Δh of the static liquid.

• Second Condition

  • The second condition of static equilibrium says that the net torque acting on the object must be zero.
  • A child's seesaw, shown in , is an example of static equilibrium.
  • An object in static equilibrium is one that has no acceleration in any direction.
  • If a given object is in static equilibrium, both the net force and the net torque on the object must be zero.
  • The system is in static equilibrium, showing no acceleration in any direction.

• Static Electricity, Charge, and the Conservation of Charge

  • Electric charge is a physical property that is perpetually conserved in amount; it can build up in matter, which creates static electricity.
  • Static electricity is when an excess of electric charge collects on an object's surface.
  • Static electricity can also be created through friction between a balloon (or another object) and human hair (see ).

• Conductors and Fields in Static Equilibrium

  • In the presence of charge or an electric field, the charges in a conductor will redistribute until they reach static equilibrium.
  • It should be noted that the distribution of charges depends on the shape of the conductor and that static equilibrium may not necessarily involve an even distribution of charges, which tend to aggregate in higher concentrations around sharp points.
  • Describe behavior of charges in a conductor in the presence of charge or an electric field and under static equilibrium

• First Condition

  • The condition $F_\text{net} = 0$ must be true for both static equilibrium, where the object's velocity is zero, and dynamic equilibrium, where the object is moving at a constant velocity.
  • Below, the motionless person is in static equilibrium.

• Application of Bernoulli's Equation: Pressure and Speed

  • For "ideal" flow along a streamline with no change in height, an increase in velocity results from a decrease in static pressure.
  • The kinetic energy of the fluid is stored in static pressure, $p_s$, and dynamic pressure, $\frac{1}{2}\rho V^2$, where \rho is the fluid density in (SI unit: kg/m3) and V is the fluid velocity (SI unit: m/s).
  • The SI unit of static pressure and dynamic pressure is the pascal.
  • Static pressure is simply the pressure at a given point in the fluid, dynamic pressure is the kinetic energy per unit volume of a fluid particle.
  • Therefore, if there is no change in potential energy along a streamline, Bernoulli's equation implies that the total energy along that streamline is constant and is a balance between static and dynamic pressure.

• Charge Separation

  • Charge separation, often referred to as static electricity, is the building of space between particles of opposite charges.
  • Because electrons are labile (i.e., they can be transferred from atom to atom) it is possible for the phenomenon of "charge separation" (often referred to as static electricity) to occur.

• Variation of Pressure With Depth

  • Pressure within static fluids depends on the properties of the fluid, the acceleration due to gravity, and the depth within the fluid.
  • At any such point within a medium, the pressure is the same in all directions, as if the pressure was not the same in all directions, the fluid, whether it is a gas or liquid, would not be static.
  • Note that the following discussion and expressions pertain only to incompressible fluids at static equilibrium.
  • The pressure exerted by a static liquid depends only on the depth, density of the liquid, and the acceleration due to gravity. gives the expression for pressure as a function of depth within an incompressible, static liquid as well as the derivation of this equation from the definition of pressure as a measure of energy per unit volume (ρ is the density of the gas, g is the acceleration due to gravity, and h is the depth within the liquid).
  • Identify factors that determine the pressure exerted by static liquids and gases