Solving Oscillation Question: Mass, Spring Constant & Frequency

[gr3g1]

I have no idea how to approach this question... Here it is:

With a block of mass m, the frequency of a block-spring system is 1.2Hz. When 50g is added, the frequency changes to: 0.9Hz Whats the mass and spring constant?

I know i have to use: T = 2pi/w = 2pi sqrt(m/k)


Thanks a lot in advanced!

 

[Ouabache]

You need to give this a try before we can help.. You probably want to reread this https://www.physicsforums.com/showthread.php?t=94379 to learn what is expected of a homework questioner.
To get you started, try and determine what the variables in your equation refer to..

$$\tau = \frac{2\pi}{\omega} = 2\pi \sqrt{\frac{m}{k}}$$

hint: you would do well to invert your expression (see ref for simple harmonic motion)

 

[Ouabache]

With your given information and using examples in your textbook, take an educated guess on how you might solve this. Once we see that you are trying, we can proceed to steer you in a successful direction.