Question

If the speed of a car is increased by 80%, by what factor will its minimum braking distance be increased, assuming all else is the same? Ignore the driver's reaction time.

Answer 1

`KE_2=3.24 * KE_1`

Step-by-step explanation:

given,

Speed of car = v

new speed of car v'= 1.8 v

Kinetic energy of the car

`KE_1 =(1)/(2)mv^2`

new Kinetic energy of energy

`KE_2 =(1)/(2)mv'^2`

`KE_2=(1)/(2)m(1.8v)^2`

`KE_2=3.24 * (1)/(2)mv^2`

`KE_2=3.24 * KE_1`

hence, the kinetic energy is increased by the factor of 3.24.