# Thread: Simple Harmonic Motion

1. ## Simple Harmonic Motion

A particle is oscillating in simple harmonic motion with period 4.5 ms and amplitude 3.0 cm. At time t = 0, the particle is at the equilibrium position. Calculate, for this particle:

a) frequency
b) the angular frequency
c) the maximum speed
d) the maximum acceleration
e) the speed at time t = 1.0 ms

My Attempt

a) 220 Hz
b) 1.4 x 10^3 rad/s
c) 42 m/s
d) 5.9 x 10^4 m/s^2

I am stuck at (e) and just don't know how to do this. Thanks for your help in advance!

2. The speed at time t = t is given by:

$v = x_o \omega sin(\omega t)$

You can find the speed now

I got 1.0 m/s.

EDIT: This is the wrong formula, the trig function should be cosine instead of sine. (at time t = 0, speed is maximum, hence...)

3. Firstly there is a "negative / -" sign in that formula and secondly that's not the correct answer I got 41.9 with that formula, don't know how you got 1.0 m/s lol

The correct Velocity is 7.1 m/s.

Anymore help guys?

4. Sorry, I gave the wrong formula.

The formula is:

$v = x_o\omega cos(\omega t)$

And I forgot to put my calc mode on radians.

Yes, I get 7.1 m/s

5. Oh shoot I think that is what I was doing wrong as well :/ Not changing into radian mode

Thanks!