(u) = 20 m/s
(v) = 0 m/s
<span> (t) = 4 s
</span>
<span>0 = 20 + a(4)
</span><span>4 x a = -20
</span>
so, the answer is <span>-5 m/s^2. or -5 meter per second</span>
This would be an illustration of Newton's first law of motion. Law of inertia, an object moving at constant velocity will keep moving at constant velocity until a force is acted upon it. Inertia is the tendency of an object to keep moving in a particular direction resisting to change, unless a force acts upon the object.
The duck at 12m/s has a greater speed than the heron which travels at 10m/s