Thanks Definition and 207 Threads

Photoelectric effect question, help please, thanks! In the standard experiment the stopping voltage is measured for several wavelengths of incident light. In this apparatus the photocathode is metallic potassium. Suppose that the apparatus has not been used for some time and that its...

1) Diffraction is a result of reflection or interference? 2) angle of reflection is _same __ as the incident angle? :confused:

A person hums into the top of a well and finds that standing waves are established at frequency of 42,000, and 98 Hz. The frequency of 42 Hz. is not necessarily the fundamental frequency. The speed of sound is 343 m/s. How deep is the well?

Hi all. It is good to see all this beautiful work being done here. Thanks to Selfadjoint and all the mentors and moderators, as well as the contributers to this and the other physics forums. The mathematics of quanta seem to indicate that there is a smallest possible quantity to any...

again, I've another question i wish it is the last. it is about "Mean Value Theorem", * if u and v are any real numbers, then, prove that: |sin(u)-sin(v)|<=|u-v| * Prove that [(1+h)^(1/2)] < [1+(h/2)], for h>0 * Suppose that f'(x)=g'(x)+x for every (x) in some interval (I)...

So basically, I've come to the conclusion that i suck. And it kinda bothers me. So i quit. I'm just done. I uh, i spose i wanted to say goodbye to everyone. Its been swell. Its a great site greg, you should be proud. And everyone's pretty cool. I learned a lot and had fun. Its been a great...

Hello,, I have a question that puzzle me for a long time! This question is: a- How an object -either metal or any thing- fly or move in air without changing in its direction. b- what field of physics study such matters? c- Is there any websites may give me detailed information about...