Respuesta :

Speed is a scalar quantity given by the rate of change in distance. Thus, it is given by distance covered divided by the time taken to cover the distance.
 Speed= distance/time
therefore, speed is directly proportional to the distance covered if time taken is kept constant, such that an increase in distance causes a corresponding increase in speed and vice versa, hence if the speed triples then you will need thrice times the distance to stop. 
skyluke89

Answer:

9 Times

Explanation:

The stopping distance of a car (or any traveling object) is proportional to the square of the speed of the car.

This is a consequence of the work-kinetic energy theorem, which states that the work done on the car is equal to its loss of kinetic energy:

[tex]W=K_i-K_f[/tex]

Since the final speed of the car is zero, its final kinetic energy, so we can write:

[tex]W=K_i\\Fd=\frac{1}{2}mv^2[/tex]

where

F is the force that stops the car (the force of friction)

d is the stopping distance

m is the mass of the car

v is the initial speed of the car

As we see from the equation, the stopping distance (d) depends on the square of the speed ([tex]v^2[/tex]). Therefore, it the speed is tripled, the stopping distance will acquire a factor [tex]3^2 = 9[/tex], so we will need 9 times the distance to stop.

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