With question. an accident investigator measured the skid marks of one of the vehicles involved in an accident. the length of the skid marks was 175 feet. what was the speed of the vehicle before the brake were applied?

The speed of the vehicle before the brake were applied was about 80 feet/s

Acceleration is rate of change of velocity.

a = acceleration ( m/s² )

v = final velocity ( m/s )

u = initial velocity ( m/s )

t = time taken ( s )

d = distance ( m )

Let us now tackle the problem!

This problem is about Deceleration

Given:

final speed = v = 0 m/s

length of skid marks = d = 175 feet

maximum deceleration = a = 20 feet/s² ( assumption )

Unknown:

initial speed = u = ?

Solution:

We will solve this problem by using following formula:

Grade: High School

Subject: Physics

Chapter: Kinematics

Keywords: Velocity , Driver , Car , Deceleration , Acceleration , Obstacle , Braking , Deceleration , Skid Marks

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have