Question

As part of a safety investigation, two 1300 kg cars traveling at 17 m/s are crashed into different barriers. Find the average forces exerted on:
a. the car that hits a line of water barrels and takes 1.5 s to stop
b. the car that hits a concrete barrier and takes 0.10 s to stop.

Answer 1

Answer:

a.  F = 14,733.33 N

b. F = 221,000 N

Explanation:

Given;

mass of the cars, m = 1300 kg

velocity of the cars, v = 17 m/s

time taken for the first car to stop after hitting a barrier, t = 1.5 s

time taken for the second car to stop after hitting a barrier, t = 0.1 s

The average forces exerted on each car is calculated as follows;

a. the car that hits a line of water barrels and takes 1.5 s to stop

$F = ma = m\times \frac{v}{t} = 1300 \times \frac{17}{1.5} = 14,733.33 \ N\\\\F = 14,733.33 \ N$

b. the car that hits a concrete barrier and takes 0.10 s to stop

$F = ma = m\times \frac{v}{t}= 1300 \times \frac{17}{0.1} = 221,000 \ N\\\\F = 221,000 \ N$