Convection is usually described as a ; when something is heated, it rises, cools, and then falls in a circular pattern.

Current

Explanation:

Convection is the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat. Simply put, Convection is the circular motion that happens when warmer air or liquid — which has faster moving molecules, making it less dense — rises, while the cooler air or liquid drops down.

An everyday example of convection is boiling water ; The heat passes from the burner into the pot, heating the water at the bottom. The water at the bottom rises and is replaced by the water at the top of the pot.

This rise of less dense water at a higher temperature and fall of denser water at a lower temperature sets up a convention current circularly until the water boils. This is a typical example of the day to day application of convection currents.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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the rearrangement of particles in a physical change. hope this