It should be C. If the object is denser than the fluid, it will sink. If it isn't, it will float
The box is accelerated from rest to 4 m/s in a matter of 2.5 s, so its acceleration <em>a</em> is such that
4 m/s = <em>a</em> (2.5 s) → <em>a</em> = (4 m/s) / (2.5 s) = 1.6 m/s²
Then the force applied to the box has a magnitude <em>F</em> such that
<em>F</em> = (10 kg) (1.6 m/s²) = 16 N
It'll certainly seem like it, because the water will get cold. But cold is not a thing. Heat is. What actually happens is that heat from the water flow into the ice (and melts it).
Answer: 154.08 m/s
Explanation:
Average acceleration
is the variation of velocity
over a specified period of time
:

Where:

being
the initial velocity and
the final velocity

Then:

Since
:

Finding
:


Finally:
