An advertisement claims that a particular automobile can "stop on a dime". what net force would be necessary to stop a 900 kg automobile traveling initially at 54.0 km/h in a distance equal to the diameter of a dime, 1.8 cm?

Force applied will be equal to 5625000 N

Explanation:

We have given mass of the automobile m = 900 kg

Initial velocity of the automobile u = 54 km/hr

As 1 km = 1000 m and 1 hour = 3600 sec

So

As the automobile finally stops so final velocity v = 0 m/sec

Distance after which automobile stops s = 1.8 cm = 0.018 m

From third equation of motion

From newtons force on any object is equal to F = ma

So force

So force applied will be equal to 5625000 N

a straight line sloped