what is simple harmonic motion
a specific type of oscillation where there is repetitive movement back and forth through an equilibrium or central position
what is restoring force
the force responsible for the simple harmonic motion
what are example of oscillators that undergo simple harmonic motion
- the pendulum of a clock
- a child on a swing
- the vibrations of a bowl
- a mass on a spring
- guitar strings vibrating
in SHM which way is the directions of the equilibrium
it is always towards the equilibrium position (centre)
an oscillation is defined to be in SHM when…
- the acceleration is proportional to the displacement
- the acceleration is in the opposite direction to the displacement
what is newton’s second law
the greater the resultant force is, the greater the acceleration will be
what is centripetal acceleration
the acceleration of the particles moving in a circular path
what is the equation for displacement in a displacement SMH graph
x= Acoswt
what is the equation for velocity in a velocity SMH graph
v = -Awsinwt
what is the equation for acceleration in an acceleration SMH graph
a- - w^2 x
what is damping
the reduction in energy and amplitude of oscillations due to resistive forces on the oscillating system
in SMH what happens to the frequency of damped oscillations as amplitude decreases
the frequency does not change
what are the four degrees of damping
light damping
heavy damping
critical damping
over damping
what is light damping
amplitude decreases with time
what is heavy damping
there are hardly any oscillations since they die out quickly e.g. a damped pendulum
what is critical damping
the oscillations are stopped as soon as possible without actually oscillating
what is over damping
there are no oscillations and the object has taken a long time to return to the equilibrium position
when do free oscillations occur
when there is no transfer of energy to or from the surroundings, this happens when an oscillating system is displaced and then left to oscillate
what is a free oscillation
an oscillation where there are only internal forces (and no external forces) acting and there is no energy input
how does a free vibration oscillate
it oscillates at its resonant (natural) frequency
what are forced oscillations
oscillations acted on by a periodic external force where energy is given in order to sustain oscillations
what is driving frequency
the frequency of the forced oscillations
what is natural frequency
the frequency of an oscillation when the oscillating system is allowed to oscillate freely
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3- quantum phenomena49
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11- materials28
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6+7 forces in equilibrium + on the move18
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Waves and optics89
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8- newtons laws of motion6
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9- forces and momentum10
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10- work, energy and power10
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circular motion10
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19- thermal physics19
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18- simple harmonic motion27
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fields97
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20- gases22
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nuclear physics31
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turning points27
