Quick Homework Help

# First of all, thank you so much for such an insightful and helpful video! There's only one problem I'm having. No matter how I calculate the last problem, I always get 3.9769 x 10 ^ (-19). What am I doing wrong? ⚑ Flag

by Byrdie1995 at September 04, 2011

calculation problem

There is no video link. What is the problem set up? Planck's hypothesis relates to wavelengths of particles, Heisenberg uncertainty and energies of photons. You've included no units (always include units!!!!) so there is no telling where the problem may lie. Please come back with more information on the problem.

kroo_jteague September 05, 2011

There is no problem, every once in a while when doing calculations your calculator has to truncate/round answers waaaay right of the decimal, this creates very small errors in calculations that you rarely see. Usually we notice it when we're looking for a 0 result and the calculator can still "see" odd decimal values, like ten to the power of negative 19. So your answer looks like: 0.00000000000000000039769, or so close to zero as makes little difference. Don't worry, everything is fine

SerTorm September 08, 2011

Let that be a lesson to me, always watch the video.   Many appologies Byrdie, I watched the video and now see what your talking about, my bad.   I still don't think you have a problem, though.  At the end of the video, he's figuring the power of ten by which the answer is multiplyied, and does a quick look at his notes to avoid the simple math -34 + 8 + 7 and reads the answer as -21.  That seems to me to be in error, as you also said, the result should be  3.9769 * 10 ^ (-19)

SerTorm October 28, 2011