Ch 7 Physics Class 9
Important Easy Notes of Ch 7 Physics Class 9 English Medium written by Professor Mr. Samiullah Suib. These notes are very helpful in the preparation of Physics for students of the 9th class Physics English Medium and these are according to the paper patterns of all KPK Book Boards.
Summary and Contents:
Topics which are discussed in the notes are given below:
- Definition of kinetic molecular model of matter and main points of kinetic model of matter.
- Explanation of three States of matter on the basis of kinetic molecular model of matter.
- Definition of solids with examples.
- Properties of a solids.
- Definition of Liquids with examples.
- Properties of a Liquids.
- Definition of Gases with examples.
- Properties of a Gases.
- Write history and definition of Plasma with examples.
- Write uses of Plasma.
- Definition of Density: symbol, mathematical form, unit, quantity, nature, and factors.
- Definition of Pressure: symbol, mathematical form, unit, quantity, nature, and factors.
- Definition of atmosphere: Range, Explanation.
- Definition of atmospheric pressure.
- Definition of barometer and write its working.
- Definition of Standard Atmospheric Pressure.
- Applications of atmospheric pressure.
- Write history and statement of a pascal principle.
- Applications of Pascal's principle.
- Definition of liquid pressure: symbol, Mathematical Form, and Explanation.
- Properties of fluids and pressure.
- Meanings and definition of Up-thrust and buoyancy.
- Write history and statement of Archimedes principle.
- Archimedes principle is applicable on liquids as well as gases.
- State and explain Law of Flotation.
- Definition of elasticity.
- Definition of deforming force.
- Definition of factor of elasticity with examples.
- Classification of material on the base of elasticity.
- Definition of Elastic material with examples.
- Definition of Non-elastic material with examples.
- Definition of elastic limit with explanation.
- Write history proposal statement of Hook's law.
- Definition of Stress: symbol, mathematical form, unit, quantity, nature, and factors.
- Definition of Strain: symbol, mathematical form, unit, quantity, nature, and factors.
- Tensor Quantity: A quantity which has magnitude as well as direction but not follow the vector laws of addition.
- Definition of a stress-strain curves.
- If you climbed a mountain carrying a Mercury Barometer, would the level of the Mercury column in the glass tube of the barometer increase or decrease as you climb the mountain? Explain.
- Walnuts can be broken down in the hand by squeezing two together but not one. Why?
- Why is the cutting edge of the knife made very thin?
- Why water tanks are constructed at the highest level in your houses?
- Why does a small needle sinks in the water and hug ships travel easily in the water without sinking?
- Explain how and why camels have adapted them to allow to walk more easily on desert condition?
- You would have probably experienced your ears "popping" while driving in the mountains. why ear pops?
- If you feel an air tight balloon at the top of a mountain would the balloon expand or contract as you decent the mountain? Explain.
- A rowboat is floating in a swimming pool when the anchor is dropped over the side when the anchors is dropped will the water level in the swimming pool increase, decrease, remain the same? explain.
- Which material the most elastic steel or a rubber and why?
- Solved Numerical of the exercise Ch 7 Physics Class 9.
- A rectangular glass block of dimensions 30 cm by 5 cm by 10cm weight 37.5N. Calculate the least and the greatest pressure it can exert when resting on horizontal body?
- What is the height of water barometer at atmospheric?
- The deepest point in the ocean is 11km below sea level, deeper than Mount Everest is tall. What is the pressure in the atmosphere at this depth?
- A block is fully immersed in water before the immersion the block weighted 30N and while immersed its apparent weight was found to be 25N. Calculate the (a) Up-thrust on the block. (b) The weight of the water displaced. (c) The volume of water displaced. (d) The volume of the block. (e) The density of the block.
- When a weight of Block 30N is hung from a wire of original length at 2.0m. Its new length become 2.20m. Calculate the force constant for the wire if the elastic limit is not exceeded?
- An 80cm long, 1.0mm diameter steel guitar string must be tightened to a tension of 2000N by turning the turning screws. By how much is the string stretched?