The question here is how long does it take for a falling
person to reach the 90% of this terminal velocity. The computation is:
The terminal velocity vt fulfills v'=0. Therefore vt=g/c,
and so c=g/vt = 10/(100*1000/3600) = 36,000/100,000... /s. Incorporating the
differential equation shows that the time needed to reach velocity v is
t= ln [g / (g-c*v)] / c.
With v=.9 vt =.9 g/c,
t = ln [10] /c = 6.4 sec.
Answer:
25
Step-by-step explanation:
The angle at C is 90 degrees, and BCD is a right triangle, so we can applythe Pythagorean theorem here -- 60²+m²=65², so 65²-60²=m²=625. The possible values for m are 25 and -25, and since m can't be negative, 25 is our answer as 25 is the square root of 625