displacement

Examples of displacement in the following topics:

• Flotation

  • But the Archimedes principle states that the buoyant force is the weight of the fluid displaced.
  • When any boat displaces a weight of water equal to its own weight, it floats.
  • The same is true for vessels in air (as air is a fluid): A dirigible that weighs 100 tons displaces at least 100 tons of air; if it displaces more, it rises; if it displaces less, it falls.
  • If the dirigible displaces exactly its weight, it hovers at a constant altitude.
  • The volume submerged equals the volume of fluid displaced, which we call $V_\mathrm{fl}$.

• Reference Frames and Displacement

  • Frames of reference are particularly important when describing an object's displacement.
  • Displacement is the change in position of an object relative to its reference frame.
  • The word "displacement" implies that an object has moved or has been displaced.
  • where Δx is displacement, xf is the final position, and x0 is the initial position.
  • Notice that the arrow representing his displacement is twice as long as the arrow representing the displacement of the professor (he moves twice as far).

• Force in the Direction of Displacement

  • The work done by a constant force is proportional to the force applied times the displacement of the object.
  • As we have shown, this is proportional to the force and the distance which the object is displaced, not moved.
  • Calculate the work done on the box if the box is displaced 5 meters.
  • (1.b) Since the box is displaced 5 meters and the force is 2 N, we multiply the two quantities together.
  • Regardless of how long it takes, the object will have the same displacement and thus the same work done on it.

• Average Velocity: A Graphical Interpretation

  • Average velocity is defined as the change in position (or displacement) over the time of travel.
  • In contrast, average velocity is defined as the change in position (or displacement) over the total time of travel .
  • When calculating average velocity, however, you are looking at the displacement over time.
  • Because you walked in a full rectangle and ended up exactly where you started, your displacement is 0 meters.
  • Therefore, your average velocity, or displacement over time, would be 0 m/s.

• Position, Displacement, Velocity, and Acceleration as Vectors

  • Position, displacement, velocity, and acceleration can all be shown vectors since they are defined in terms of a magnitude and a direction.
  • Most commonly in physics, vectors are used to represent displacement, velocity, and acceleration.
  • In physics, vectors are useful because they can visually represent position, displacement, velocity and acceleration.
  • Displacement is defined as the distance, in any direction, of an object relative to the position of another object.
  • Physicists use the concept of a position vector as a graphical tool to visualize displacements.

• The Simple Pendulum

  • For small displacements, a pendulum is a simple harmonic oscillator.
  • We begin by defining the displacement to be the arc length s.
  • The displacement s is directly proportional to θ.
  • where the force constant is given by k=mg/L and the displacement is given by x=s.
  • The linear displacement from equilibrium is s, the length of the arc.

• Simple Harmonic Motion

  • Simple harmonic motion is a type of periodic motion where the restoring force is directly proportional to the displacement.
  • Simple harmonic motion is a type of periodic motion where the restoring force is directly proportional to the displacement (i.e., it follows Hooke's Law) .
  • where m is the mass of the oscillating body, x is its displacement from the equilibrium position, and k is the spring constant.
  • Each of these constants carries a physical meaning of the motion: A is the amplitude (maximum displacement from the equilibrium position), ω = 2πf is the angular frequency, and φ is the phase.
  • Relate the restoring force and the displacement during the simple harmonic motion

• Pictures of Modes

  • ., places where the displacement is zero).
  • These are two snapshots of the instantaneous displacement of the plane when being driven in one of its modes.

• Conditions for Wave Interference: Reflection due to Phase Change

  • When two or more waves are incident on the same point, the total displacement at that point is equal to the vector sum of the displacements of the individual waves.
  • If a crest of one wave meets a crest of another wave of the same frequency at the same point, then the magnitude of the displacement is the sum of the individual magnitudes.
  • In this case, the magnitude of the displacements is equal to the difference in the individual magnitudes, and occurs when this difference is an odd multiple of π.
  • If the difference between the phases is intermediate between these two extremes, then the magnitude of the displacement of the summed waves lies between the minimum and maximum values.

• Longitudinal Waves

  • Like transverse waves, longitudinal waves do not displace mass.
  • It is important to remember that energy, in this case in the form of a pulse, is being transmitted and not the displaced mass.
  • Matter in the medium is periodically displaced by a sound wave, and thus oscillates.