Question

A meter stick is held vertically above your hand, with the lower end between your thumb and first finger. On seeing the meter stick released, you grab it with these two fingers. You can calculate your reaction time from the distance the meter stick falls, read directly from the point where your fingers grabbed it.


If the measured distance is 18.2 cm , what is the reaction time?


t= s

Answer 1

Assuming you mean 18.1 cm.
x = at^2/2 ==> t = sqrt(2x/a)
a = g = 9.81 m/s^2
2x = 0.362
t = 0.1921 s.
it is right but you enter 18.2
ok