# Effect on angular frequency in a sping mass system

1. Apr 9, 2010

### DR1

i am trying to work this out from a very confusing book what would the effect on angular frequency be by

increasing mass
increasing amplitude of vibration
increasing spring stiffness
increasing phase lag

need to get this in my head before attemping to work out questions

2. Apr 9, 2010

### bp_psy

What do you think the effects would be?

3. Apr 9, 2010

### DR1

an increased mass would lead to an increased angular frequency
amplitude of vibration would again increase as its multiplied through w
it would have no effect on spring stiffness as i don't see any formule that use both parts but then having said that if it increases the mass that would have an effect on the sping stiffness
the phase lag would increase w as (wt+0) as such they are linked together

you dont have to tell me the answers even pointing me in the right direction would help

4. Apr 9, 2010

### bp_psy

Consider that for the spring mass oscillator $$\omega=\sqrt{\frac{k}{m}}$$.This tells you that the only factors that affect the natural angular frequency is determined by the physical properties of the system.So increasing the mass actually lowers the angular frequency.This is because a more massive object is harder to accelerate(second law).
No the angular frequency is independent of amplitude. .What do you mean by"multiplied through w"
Again look at this $$\omega=\sqrt{\frac{k}{m}}$$ angular frequency is determined ONLY by m and k in SHM. A stiffer spring is capable of applying more force on the mass remember F=-kx(again the second law). The phase only tells you at what angle your rotating vector is at t=0 so it does not effect angular frequency

5. Apr 9, 2010

### DR1

Thankyou very much for your assistance it all makes alot more sense when its all writen down in one place not over a whole book.