Class 9 Physics Chapter 7 Exercise Constructive Questions PDF New Syllabus

Download Class 9 Physics Chapter 7 Exercise Constructive Questions PDF both English and Urdu medium for quick revision and exam preparation. This PDF is helpful for 9th class students who want to prepare important exercise comprehensive questions according to the new syllabus. Students can use it to revise chapter-wise questions, improve their concepts, and prepare better for school tests and board exams.

Chapter 7 Constructive Questions: Thermal Properties of Matter

The constructive questions at the end of Chapter 7 describe a situation and ask you to account for it. They are the closest thing in the textbook to the nine-mark questions in the annual paper. In this chapter they deal with:

• Why two bodies at the same temperature can hold very different amounts of heat.
• How the kinetic molecular model accounts for the three states of matter.
• Why water is used as a coolant in machinery.
• When a thermocouple is a better choice than a mercury thermometer.

What a Full-Mark Answer Looks Like Here

These answers are marked point by point, so an answer that circles the idea without stating it plainly scores badly. For Thermal Properties of Matter in particular:

• Separate the quantity of heat from the temperature at every step.
• Refer to molecular spacing and motion when explaining a change of state.
• Name the law or principle first, then apply it to the objects actually named in the question.
• Draw and label a diagram wherever one is possible, since it often carries a mark by itself.

Why This Set Repays the Effort

Most students drill the short questions and leave the constructive ones until last, which is the wrong way round. Eighteen of the sixty marks in the annual paper come from long questions built on exactly this material, and a reasoning question cannot be answered from memory alone. Attempt them in writing with the book closed, then compare.

Frequently Asked Questions

Why is water used as a coolant?

Because it has an unusually high specific heat capacity, so it absorbs a large quantity of heat for a small rise in its own temperature.

How many marks do the long questions carry?

Eighteen of the sixty. Three are offered and you attempt any two, at nine marks each, split into a four-mark and a five-mark part.

Related Class 9 Physics Resources

For the two-mark recall answers from the same chapter see the Chapter 7 exercise short questions, and check your understanding with the Chapter 7 online test. Continue with Chapter 6 and Chapter 8, or download the 25 Class 9 Physics guess papers for timed practice. Browse Class 9 Physics notes for the rest.