Answer:
B. A large number of atoms move from one place to another
Explanation:
Convection is heat transfer by the movement of atoms of a substance from one region to another across a temperature gradient. Since atoms of solids are rigidly held in place, convection only occurs in liquids and gases since they flow.
Convection occurs when the temperature of one region of a fluid (liquid or gas) is higher than its other region. There is thus a mass movement of atoms from one region to the other due to a temperature difference. The atoms will continue to move to the region of lower temperature until the temperature of both regions are the same at an equilibrium temperature.
We use the formula,
Here, h is the variable represents the height of the flare in feet when it returns to the sea so, h = 0 and u is the initial velocity of the flare, in feet per second and its value of 192 ft/sec.
Substituting these values in above equation, we get
.
Here, t= 0 neglect because it is the time when the flare is launched.
Thus, flare return to the sea in 12 s.