Absolute zero is the temperature where atoms and molecules have no vibrational motion and cease all movement. As temperature increases, the kinetic energy and velocity of gas molecules increases. For liquids, the random motion of molecules increases with temperature. Heating a solid causes its dimensions, such as length, to change. We are unaware of fast-moving air molecules colliding with our bodies because the forces from collisions cancel out due to air molecules colliding from all directions.

1. 10.-17.14 pointsOBIn Phys7 5.2.003. What is the significance of absolute zero? This answer has
not been graded yet. Show My Work (Optional) 11.-/7.14 points OBIn Phys7 5.2.004. What
happens to the atoms and molecules in a substance as its temperature increases? This answer has
not been graded yet. Show My Work (Optional) 12.-17.14 pointsOBIn Phys7 5.2.006. Air
molecules in a warm room (27°C = 300 K) typically have speeds of about 500 m/s (1,100
mph). Why is it that we are unaware of these fast-moving particles continuously colliding with
our bodies? Because the air molecules are everywhere around us they constantly collide with our
bodies from all directions. The effect of these collisions tend to cancel out. The density of the
warm air is so low that the air molecules tend to miss our bodies The mass of an air molecule is
so miniscule that its momentum and kinetic energy are too small to be evident in the collision
with a human body. The size of an air molecule is extremely small, so its momentum and kinetic
energy are not efficiently transferred to our bodies when the collisions with a human body occur.
Show My Work (Optional)
Solution
Significance of Absolute Zero
Absolute Zero is that temperature where the fundamental particles (atoms and molecules) of
nature have minimal vibrational motion. Absolute Zero is the temperature 0K or -273*C. At
absolute zero the gaseous molecules seized to move as they donot posses any energy and their
entropy is zero.
Temperature Increase
When temperature is increased the kinetic energy of the atoms and molecules of a gas increases
which increase their velocity.
In case of liquid they when the temperature increases them random motion of the molecules
increases.
If the substance is a solid then it gets heated up and its dimensions may change. For example
when we heat a rod it's length gets increased.
12. Option A.

2. Air molecules are all around and forces exerted by them gets cancelled out.