View and Download the solved questions, solved numerical problems or 9th Class Physics notes of Chapter 7 “Properties of Matter” of Punjab Textbook Board. These 9th class physics notes of 7th Chapter are according to the new syllabus (2013) of Punjab Boards including Lahore Board, Gujranwala Board, Sahiwal Board, Rawalpindi Board, Faisalabad Board, Multan Board, Bahawalpur Board, Federal Board, DG Khan Board and Sargodha Board. Students of 9th Class of all these board can facilitate from the physics notes given below. You can also download 9th Class Physics Chapter 7 Solved Questions and Numerical Problems.

### Unit 7: Properties of Matter

By studying this chapter students will be able to: State kinetic molecular model of matter (solid, liquid and gas forms). Describe briefly the fourth state of matter i.e. Plasma. Define the term density. Compare the densities of a few solids, liquids and gases. Define the term pressure (as a force acting normally on unit area). Explain how pressure varies with force and area in the context of everyday examples. Explain that the atmosphere exerts a pressure. Describe how the height of a liquid column may be used to measure the atmospheric pressure. Describe that atmospheric pressure decreases with the increase in height above the Earth’s surface. Explain that changes in atmospheric pressure in a region may indicate a change in the weather. state Pascal’s law. Apply and demonstrate the use with examples of Pascal’s law. State relation for pressure beneath a liquid surface to depth and to density i.e.,(P=pgh) and solve problems using this equation. State Archimedes principle. Determine the density of an object using Archimedes principle. State the upthrust exerted by a liquid on a body. State principle of floatation. Explain that a force may produce a change in size and shape of a body. Define the terms stress, strain and Young’s modulus. State Hooke’s law and explain elastic limit.