The brakes on your automobile are capable of creating a deceleration of 4.7 m/s2. If you are going 141 km/h and suddenly see a state trooper, what is the minimum time in which you can get your car under the 76 km/h speed limit

The minimum time taken is 3.84 s.

Explanation:

The expression for the equation of motion is as follows;

v= u+at

Here, v is the final speed, u is the initial speed, a is the acceleration and t is the time.

Convert the initial speed from to .

Convert the final speed from to .

It is given in the problem that The brakes on your automobile are capable of creating a deceleration of . The sign of the acceleration is negative here as there is deceleration.

Calculate the minimum time by using equation of motion.

v= u+at

Put , and

21.11= 39.17+(-4.7)t

t= 3.84 s

Therefore, the minimum time taken is 3.84 s.

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

what is the actual question though?