Loc: Boston,Massachusetts U.S.A. I have a question on wedding traditions, I was hoping that you might enlighten me.. In Spain the wedding ring is put on the right hand while in the U.S it is on the left hand..
Doppler assessment of area by pressure half-time method ï§ The time required for the mitral diastolic pressure to fall by 50% ï§ Mitral valve area is calculated as: 220 â pressure half time (msec).
A typical radioactive decay problem might say, after two days, a sample of carbon-14 has decayed 75%, so what is the half-life? To make the problem easy, assume 100 grams for the original mass. So 75 = 100e^2k, or 0.75=e^2k. Take the ln (the log) of both sides. A graphing calculator gives the ln of the left side of the equation. The ln of e is equal to the power of e. So the ln of e^2k equals 2k. Combined, the equation becomes -0.3=2k, with k equal to -0.15. To get the half life, plug k into the formula when A=1/2A0 and solve for t. In this case, the half-life is 4.67 days.