Question

Nerve impulse travel at about $100m/s.$ If a woman $1.8m$ tall steps on a drawing pin.
a) Roughly how long is it before she knows about it?
b) If she is walking along at a speed of $2m/s$ , how far will she have traveled in this time?

Answer 1

a)

Step 1: Given data
Speed of nerves impulse, V1 $=100m/s$
Height of woman, S1 $=1.8m.$

Step 2: Time taken by nerve impluse to send message to brain
Time taken by nervous impulse to send message to brain , $t=\frac{S1}{V1}=\frac{1.8m}{100m/s}=0.018seconds.$

Hence, she will know about it in $0.018seconds.$

b)

Step 1: Given data

Walking speed of woman , $V2=2m/s$
Time taken by nerve impulse ,$t=0.018seconds.$

Step 2: Calculating distance travelled by woman
Distance travelled by woman ,$S=V2\times t=2\times 0.018=0.036m.$

Hence, she travelled $0.036m$in this time.