Simple Harmonic Motion Flashcards
What is simple harmonic motion?
a common type of oscillation where an object vibrates about an equilibrium position under the influence of an unbalanced force
What must be true about the unbalanced force in simple harmonic motion?
- always directed towards the equilibrium position
* proportional to the displacement of the object from the equilibrium position
What are the equations for simple harmonic motion?
- y=Awsinwt
- y=Awcoswt
- a=-w²y
- F=-kx
What is the relationship between the spring extension and tension?
the spring extension is directly proportional to the tension in the spring
How is the constant of proportionality represented?
k
What is the opposing equal force to the stationary mass in equilibrium?
the resting force
What can be said about spring constant and resting force?
they are equal
What is the symbol for the spring constant?
k, it has the units Nm⁻¹
What is the equation for Hooke’s law?
F=ky
What is the amplitude?
the maximum displacement of an oscillating object from the zero displacement (equilibrium) position
What is the frequency of the SHM?
the number of complete oscillations performed
For an object to be performing simple harmonic motion what must the net force acting on it be proportional to?
displacement
What quantity is continuously changing as an object oscillates?
acceleration
What happens as the displacement of the mass increases?
the velocity decreases therefore the kinetic energy of the mass decreases
What happens to the lost energy in SHM?
it is stored as potential energy in the spring
What is the relationship between elongation and potential energy?
The more the spring is stretched or compressed the greater the potential energy stored in it
What is the case when the kinetic energy is at a maximum?
when the speed of an oscillating object is at a maximum, this is when the displacement (y) =0
What happens when y=a?
- the velocity is momentarily zero and so the kinetic energy is zero
- the restoring force acting on the object is at a maximum at this point and so the potential energy is at a maximum
A mass attached to a spring is oscillating horizontally on a smooth surface. At what point in its motion does kinetic energy have a maximum value?
when the displacement from the rest position is zero
What does A equal?
amplitude
What is the equation for kinetic energy?
Ek=1/2mw^2(A^2-y^2)
What is the equation for potential energy?
Ep=1/2mw^2y^2