Estimate the acceleration you subject yourself to if you walk into a brick wall at normal walking speed. Make a reasonable estimate of your speed and the time it takes you to come to a stop. Explain your answer!

Walking into a brick wall at normal walking speed (1.4 m/s), you will come to a complete stop in a short time (0.1 s) and experience much more acceleration (14 m/s²) back the way you came, but because you are softer than the wall, the inelastic collision will probably cause you to bounce back off the wall, changing the actual experienced acceleration you feel.

Explanation:

Assuming normal human walking speeds and time it takes to come to rest.

Normal human walking speed = 5km/h = 1.4 m/s

Time it takes you to come to a complete stop = 0.1 seconds

acceleration = Δ Velocity / Time

Δ Velocity = final velocity - initial velocity

Δ Velocity = (1.4 - 0) m/s = 1.4 m/s

acceleration = 1.4/0.1

acceleration = 14 m/s²

Walking into a brick wall at normal walking speed, you will experience much more acceleration back the way you came, but because you are softer than the wall, the inelastic collision will probably cause you to bounce back off the wall, changing the actual experienced acceleration you feel.