simple harmonic motion
Physics and electronics discussion, revision, exam and homework help.
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simple harmonic motionhey guys,
i cant understand how in SHM the acceleration is maximum in a pendulum/spring-mass system when then the velocity is negative.
i get it mathematically because at the point where V=0 the gradient is maximum negative/positive so therefore Acceleration is maximum negative or positive, but i dont understand it theoretically.
is the restoring force the unbalanced net force on the system?
resultant force =ma
is the net force on the system =
Driving force-restoring force=ma or = -kx ?
or is there no driving force? its just that i dont know what the force that is opposing the restoring force?
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Re: simple harmonic motionThe greatest acceleration is not when velocity is negative, it's when it is zero.
Theoretically this should make sense since if acceleration is the rate of change of velocity, then the "greatest change" in this case is when the pendulum/mass changes direction - but to change direction it needs to stop moving in one direction before it can move in another - so there is a snapshot in time where v=0.
As for "Driving force-restoring force=ma or = -kx ?"; It's both. You equate them to get ma=-kx, which is the differential equation that defines SHM. -
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Re: simple harmonic motionthank you that makes sense(Original post by FireGarden)
The greatest acceleration is not when velocity is negative, it's when it is zero.
Theoretically this should make sense since if acceleration is the rate of change of velocity, then the "greatest change" in this case is when the pendulum/mass changes direction - but to change direction it needs to stop moving in one direction before it can move in another - so there is a snapshot in time where v=0.
As for "Driving force-restoring force=ma or = -kx ?"; It's both. You equate them to get ma=-kx, which is the differential equation that defines SHM.
