Why does a mass on a spring oscillate?

[saltrock]

Mass on a spring!Please respond urgently !

When the mass is attached on one end of the string , it oscillates.with refrence to the tension and weight,explain why it oscillates.
ans: *when the mass it attached then mg> T so it goes down
* when it goes down then T>mg so it goes up and repeats the same process...

please help me write a good answer for this.

 

[garytse86]

it won't oscillate until you start it with an input of energy and then it vibrates until energy dissipated to the surroundings, e.g. by damping (due to fluid resistance etc)
Just state that acceleration is directly proportional to displacement and is always towards an equiilbrium point.

Not sure if this helps tho.

 

[Sirus]

When the mass is attached on one end of the string , it oscillates.with refrence to the tension and weight,explain why it oscillates.
ans: *when the mass it attached then mg> T so it goes down
* when it goes down then T>mg so it goes up and repeats the same process...

please help me write a good answer for this.

I think what you were getting at here is also good to add. Because $F_{spring}=-kx$, where k is the spring constant and x is the displacement from equilibrium, the force exerted by the spring on the mass increases as the spring is compressed or extended. Also consider that elastic potential energy (due to the spring) and kinetic energy are constantly interconverted during the oscillations, with max kinetic energy (and therefore max velocity) occurring when the mass passes the equilibrium point, because there elastic potential energy is zero.