Question

Nerve impulses in a human body travel at a speed of about 100 m/s. Suppose a woman accidentally steps barefoot on a thumbtack. About how much time does it take the nerve impulse to travel from the foot to the brain (in s)

Answer 1

T = 0.017 s

From the foot to the brain is almost the same as the height. We are not given the height of the woman, but to find "about" how much time, we need a height to work with.

She *could* be 1.7 m <- height = distance

Formula for speed, where k = speed, d = distance, t = time
k = d/t
Rearrange to solve for time:
t = d/k
Substitute known values:
t = (1.7 m) / (100 m/s)
Solve:
t = 0.017 s

Therefore, it takes about 0.017s for the impulse to travel from the foot to the brain.