Physics IX Notes Chapter 7 Properties of Matter
physics class 9th notes for kpk all board.
Q.1 explains the kinetic molecular model of matter?
explains the states of matter on the bases of a molecular model of matter?
solids have a definite shape and a definite volume.
In solids, molecules cannot transfer from one place to another.
Their molecules perform the vibratory motion.
Their molecules are increased with an increase in temperature.
I. Liquids have a definite volume but no definite pe.
II. Molecules in liquids are loosely bonded to each other.
III. In liquids, molecules can transfer from one place to another.
IV.Force of attraction b/w molecules is weaker than solids.
V. Their K.E increases with an increase in temperature.
they have neither definite shape nor volume.
Their molecules are at a large distance from one another.
Their molecules can move freely and perform the random motion.
Force of attraction b/w molecules in temperature.
Plasma:- this is the 4thstate matter which is found in an ionized state; it is called plasma that exists in the sun.
Define and explain “Density”?
Explanation:-if mass of a body is “m” and volume of that body is “v” then we can write its mathematical form as;
From its mathematical form, it is clear that density is the intermolecular force b/w then.
Density is a vector quantity and its unit is kg/m3.
Pressure = force/area => p = f/A
Its unit is Pascal.
Define and explain atmospheric pressure?
This is a layer of air around us which is called the atmosphere. We live in the ocean of air which exerts a force upon our body and it is equal to 100,000 Pascal which is called one atmospheric pressure.
write a note on the barometer?
write application of atmospheric pressure in our daily life?
Sucking throws straw:- when we suck any liquid through a straw the volume of lungs increases and the air pressure decreases. As a result of the atmospheric rise in straw.
Surfing:– when we draw any liquid with the help of syringe the pressure inside the syringe decreases while the pressure a surface of liquid increases which forces the liquid ongoing into the syringe.
while the pressure on the surface of liquid increases which forces the liquid ongoing into the syringe.
explains how weather changes with atmospheric pressure.
100m bar = 1 bar => 1bar = 100kpa
The atmospheric pressure usually changes from 1040 bar to as low as 950 bar. The wind moves from high-pressure regions to low-pressure regions. The winds of low-pressure areas move anticlockwise while the wind of high-pressure areas move clockwise in the northern hemisphere. The strength of the wind is determined by the pressure gradient.
state and explain Pascal’s law?
Explanation:- consider a container having four openings A, B, C and D as shown In figure. There are moveable pistons in every opening.
Now if we use this container with water or any other liquid. Then we apply some force on anyone piston of them. Suppose we apply force on “A” as soon as we apply force on piston “A” at the same time the other three pistons will also start moving outwards. This experiment shows that pressure exerted on any liquid in any container is distributed equally in all directions.