# Physics

posted by .

A 40.0 N force stretches a vertical spring 0.250 m.
(A) What mass must be suspended from the spring so that the system will oscillate with a period of 1.0 s?
(B) If the amplitude of the motion is 0.050 m and the period is as in part (a), where is the object and in what direction is it moving 0.35 s after it has passed the equilibrium position moving downwards?
(C) What force (magnitude and direction) does the spring exert on the object when it is 0.030 m below the equilibrium position, moving upward?

• Physics -

From the force and deflecion information, the spring constant is k = F/X = 160 N/m

(A) Use the equation
P (period) = 2 pi sqrt(M/k)
(Solve for M)

(B) The total energy (kinetic + potential) = (1/2) k (Amplitude)^2

If t=0 is the equilibrium position,
X = -A sin (2 pi t/P)
A = 0.050 m
Substitute t = -0.35 s
That is more than 1/4 period past the t=0 postion. It should be at negatime deflection but on the way back.

(C) X = -0.030 m. Multiply than by k for the force. The force wil be up.

## Similar Questions

Sorry for the re-post but I really need to know this, but now I just want to know if the question is right. A spring with a force of 5.2 N/m has a relaxed length of 2.45. When a mass is attached to the end of the spring and allowed …
2. ### Physics Help!

A 2.2 kg mass is attached to a spring with a force constant of 560 N/m on a smooth horizontal surface. The mass is pulled to one side, released, and allowed to oscillate back and forth. (a) find the maximum compression and expansion …
3. ### Physics

So I did in an experiment and the results I got were the potential energy when the spring compresses is 0 and when it stretches is 1.42. This spring is vertical and has a 250 gram spring attached to it. I was very confused when i got …
4. ### physics

One end of a massless coil spring is suspended from a rigid ceiling. It is found that when a 4 kg mass is suspended from it the spring stretches 90 mm when the mass comes to rest. (a) What is the spring constant for the spring B)If …
5. ### physics

One end of a massless coil spring is suspended from a rigid ceiling. It is found that when a 3.3 kg mass is suspended from it the spring stretches 105 mm when the mass comes to rest. (a) What is the spring constant for the spring?
6. ### PHYSICS

When a 0.116 kg mass is suspended at rest from a certain spring, the spring stretches 3.50 cm. Find the instantaneous acceleration of the mass when it is raised 5.70 cm, compressing the spring 2.20 cm.