Ok heres the deal. The problem gives me this wave function:(adsbygoogle = window.adsbygoogle || []).push({});

y= (15cm) cos[(pi/5cm)x - (pi/12s)t]

I undserstand that 15cm represents the amplitude, 5cm represents the wavelength, and 12s represents the T. What I dont get is that the standard wave function is in this form:

y(x,t)= A cos[(2pi/lambda)x - (2pi/T)t]

I thought I was good at algebra, but I can't seem to figure out how to the the pi's in the given equation to be at a factor of 2 with the rest of it being the same. The problem asks me to find: amplitude (which I got 15cm), the wavelength (I got 2.25cm), the T (I got 6s), and speed and direction. Please help if you can!

Thanks,

Eric

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Harmonic wave functions

**Physics Forums | Science Articles, Homework Help, Discussion**