A40000-mg ocean liner has an initial velocity of 4 km/h. neglecting the frictional resistance of the water, determine the time required to bring the liner to rest by using a single tugboat which exerts a constant force of 225 kn. (round the final answer to the nearest whole number.)

197.2 s

Explanation:

First of all, let's convert the mass of the ocean liner into kilograms:

and the initial velocity into m/s:

The force applied is

So we can find first the deceleration of the liner:

And now we can use the following equation:

with v = 0 being the final velocity, to find t, the time it takes to bring the liner to rest:

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