What’s the frequency for problem #10?

The answers penciled in on the sheet are fine ... 1500 Hz and 0.0006 sec.

If you want to get super-technical about it, you could count the number of full cycles on the WHOLE graph, from one side to the other.  At the right end, near 0.01 sec, you can notice an extra 1/4 of a cycle there.  So it's actually 15 and 1/4 cycles in 0.01 sec.

That makes the frequency (15.25 cycles) / (0.01 sec) = 1,525 Hz .

and the period ( second / 1525) = 0.000656... second.

But I think it would be OK if you didn't do that, and just call it 1500 Hz and 0.0006s.

The difference is only 1.6% , and the engineer in me says that's not enough to worry about.

explanation:

earth's surface is mainly heated by the absorption of infrared radiation from the sun.

evaporation occurs because molecules in liquid water are warmed ( usually by the sun) and vibrate quicker, becoming less dense and rise.

condensation occurs because molecules in water vapor are cooled and therefore vibrate more slowly thus becoming more dense and eventually fall to earth.

lines of equal barometric pressure on a weather map are called: isobars : lines of equal temp on a weather map are called: isotherms.​

their crystal patterns have been disrupted by stress