Question

If the speed of a car is increased by 75%, by what factor will its minimum braking distance be increased, assuming all else is the same

Answer 1

breaking distance will increase by a factor 3.0625

Step-by-step explanation:

From Newton's equation of motion, we can say that;

v² = u² + 2as

Where initial velocity is zero, we have;

v² = 2as

s = v²/2a

Where s is the distance and v is the final speed.

We will assume the deceleration(negative acceleration) is the same value,

Now, we see that the distance is directly proportional to the square of the velocity.

Now, 75% increase in speed means it has increased by a factor of 1.75

Thus means;

1.75²v² is directly proportional to the 1.75²d

Distance =

1.75²v² = 3.0625d

Thus, breaking distance will increase by a factor 3.0625