5.3 Oscillations (shm) Flashcards
What is the equilibrium position in an oscillation?
The point at which an object experiences no resultant force and thus no acceleration (the ‘rest’ position of an object).
How many radians of phase are there in one complete oscillation?
2pi
How do you calculate the angular frequency of an oscillation?
2pi x frequency of the oscillation
What are the conditions required for shm?
The acceleration of an object is proportional, to its displacement from equilibrium and always in the opposite direction
What is the acceleration of an object undergoing SHM when it’s displacement is zero?
Zero
What is an isochronous oscillator?
An oscillator with a period/frequency that is not dependent on amplitude
What is a fiducial marker?
A pin or a pointer placed at the equilibrium position of an oscillation
What measures can be taken to improve the accuracy when measuring the time period of SHM?
Time over multiple oscillations and calculate the average of several repeats.
What is the kinetic energy of an SHM oscillator at maximum displacement?
Zero
How does the total energy in an SHM oscillator vary with time?
It is constant
At what displacement is the potential energy of an SHM oscillator at a maximum?
At maximum displacement (x=±A).
How do you calculate the total energy of an SHM oscillator from its amplitude?
E = 1⁄2 k A^2
What is a free oscillation?
An oscillation in which no external driving force is present
What causes damping of an oscillation?
An external force opposing motion
What effect does damping of an oscillation have in terms of energy?
It transfers the KE of the oscillation to other forms, usually thermal energy
What is light damping of an oscillation?
A small damping force causing the amplitude of the oscillations to decrease slowly.
What is heavy damping of an oscillation?
A damping force that results in a rapid decrease in the amplitude of oscillations
What is very heavy damping of an oscillation?
A large damping force that prevents any oscillations of the system when its displaced.
What is the natural frequency of an oscillator?
The frequency at which osicllation will occur in a system with no external driving forces (free oscillations)
What is a forced oscillation?
An oscillation in which a (periodic) external driving force is present
What is a driving frequency in oscillations?
The frequency of the external driving force in a forced oscillation
What is resonance?
When the driving frequency of a forced oscillation is close to the natural frequency of the system resulting in large amplitude oscillations
What is likely to occur when a mechanical system with little or no damping resonates?
The amplitude of the oscillations will increase until the object breaks.
What occurs in terms of energy during resonance?
There is the greatest possible transfer of energy from the driver to the forced oscillation.
What effects does increasing damping have on resonance?
It reduces the maximum amplitude and it reduces the frequency of maximum amplitude
