<h2><u>Answer:</u></h2>
Cynophobia
<h3><u>Explanation:</u></h3>
Cynophobia originates from the Greek words that signify "dog" (cyno) and "fear" (phobis). An individual who has cynophobia encounters a dread of mutts that is both unreasonable and tenacious. It's something beyond feeling of scaredness whether a dog is barking or an individual is around dogs.
An individual who has cynophobia encounters a dread of dogs that is both silly and constant. Explicit fears, similar to cynophobia, influence somewhere in the range of 7 to 9 percent of the populace. They're regular enough that they're formally perceived in the Diagnostic and Statistical Manual of Mental Disorders,
To solve this problem we will apply the concepts related to the conservation of momentum. That is, the final momentum must be the same final momentum. And in each state, the momentum will be the sum of the product between the mass and the velocity of each object, then


Here,
= Mass of each object
= Initial velocity of each object
= Final velocity of each object
When they position the final velocities of the bodies it is the same and the car is stationary then,

Rearranging to find the final velocity



The expression for the impulse received by the first car is


Replacing,


The negative sign show the opposite direction.
Hooke's Law
F = k. Δx
Δx = 30 cm = 0.3 m
200 = k . 0.3

the spring stretch for 100 N:
