Question

The driver of a 2.0 × 103 kg red car traveling on the highway at 45m/s slams on his brakes to avoid striking a second yellow car in front of him, which had come to rest because of blocking ahead as shown in above Fig. After the brakes are applied, a constant friction force of 7.5 × 103 N acts on the car. Ignore air resistance.
(a) Determine the least distance should the brakes be applied to avoid a collision with the other vehicle?
(b) If the distance between the vehicles is initially only 40.0 m, at what speed would the collision occur?
(c) Write your conclusive observations on the result obtained from this numerical. i.e. the importance of Physics in daily life.

Answer 1

Answer:

Explanation:

I will tell you steps:-

Force=F=7500N

Mass=M=2000kg

Initial Velocity=Vi=45m/s

First use this formula

F/M=a

Force will be negative due to opposite direction so acceleration will also be negative but this will only show direction. We will put positive values in formulas. You must mention direction otherwise it is wrong

Part a:

Now from equation of motion

Vf^2=Vi^2-2as

Vf=0, Vi, and acceleration are known we can calculate distance

Part B:

Use same equation of motion

Vi, a and s are given simply put values in formulaa

Part C:

If there is no friction than no action will be taken. A moving body will never stop and a stationary body will never move.