Question

During a crash test, two identical cars crash into two different barriers. Both cars are initially traveling at the same constant velocity. Car A crashes into a solid brick wall and decelerates to v = 0.0m/s over a distance dA = 10.0cm. Car B crashes into a row of shrubs and decelerates to v = 0.0m/s over a distance dB = 10.0m. During the collision Car A experiences an average force FA and Car B experiences and average force FB. What is the ratio FA/FB?

Answer 1

Answer:

FA / FB = 100

Explanation:

given two identical cars

let their initial speed be U m/s

for car 1 let it deaccelerates with a1

0 = U² - 2*a1*(10cm)

a1 = U² / (2*(0.1))

car2 deaccelerates with a2

0 = U² - 2*a2*(10)

a2 = U² / (2*(10))

FA = m*a1  

FB = m*a2

FA/FB = a1 / a2

= 10/0.1

= 100

FA/FB = 100