" 20 m/s² " means that if gravity is the ONLY force on the object
(the object is in 'free fall'), then its speed increases by 20 m/s
every second.
That's the answer to your question. Now, let me ask you
another one:
How does a speedometer tied to a falling rock work ?
How can it measure the rock's speed ?
Maybe one way would be to have a little tiny propeller on
the front of the speedometer, and it could measure how fast
the propeller is spinning as the rock falls through the air ?
Great idea. But we already said the rock is in free-fall,
so there's no air resistance, we can't have any air, and
there's nothing to spin the propeller.
How would you do it ? How can you measure the rock's speed ?
The answer is C. Convection.
Radiation is the transfer of energy through electromagnetic waves. Conduction, on the other hand, is energy transfer through solid material. Condensation occurs when warm gas makes contact with a cold surface or environment, which causes a change in state from gas to liquid. These definitions rule out choices A, B, and D.
Convection is movement of particles in fluid or gas. As liquid/gas heats up, it becomes less dense and rises, moving away from the heat source. When it rises, it eventually cools down and sinks again. It is warmed up again and the cycle continues. This is why there is a circular motion when convection occurs.
A group of individuals living in a particular geographic area is termed population.
Because the specimen is very small with a light microscope
non examples of temperature are dixionanon , fairinheat, cabrowskin, and lastly ancomthere