Physics Set 9 FAQs

1. The temperature and pressure at which all three phases of a substance coexist is called its:

2. The number of base units in the SI system is:

3. Cities being warmer than their surrounding rural areas is known as the:

4. When sound travels from a source to a listener, what is transferred through the medium?

5. The lift-off of a rocket is explained by:

6. An object is placed between the pole and the principal focus of a concave mirror. The image formed is:

7. The number of neutrons in a tritium nucleus is:

8. The total mechanical energy of a particle in SHM with amplitude A and spring constant k is:

9. According to Joule's law, for a given resistance the heat produced is directly proportional to the ___ of the current:

10. Which of the following is a magnetic material?

11. Thunder is produced due to:

12. According to the work-energy theorem, the work done on an object equals:

13. According to the laws of reflection, the incident ray, the normal at the point of incidence and the reflected ray all lie in the:

14. Vibration refers to:

15. Two instruments playing the same note at the same loudness sound different because of their:

16. The star nearest to us after the Sun is:

17. A species has 10 electrons, 8 protons and 8 neutrons. It is:

18. When a bar magnet is broken into smaller pieces, each piece has:

19. The correct increasing order of penetrating power is:

20. Water rises in a narrow tube in spite of gravity. This is due to:

21. The speed of sound in water is approximately how many times its speed in air at 15 °C?

22. The temperature at which the liquid and vapour states of a substance coexist in thermal equilibrium is called its:

23. In a cyclone, the region of lowest pressure is the:

24. Consider the following pairs in Fleming's left-hand rule: (I) Forefinger – Direction of magnetic field (II) Middle finger – Direction of current (III) Thumb – Direction of current Which of the pairs given above is/are correctly matched?

25. Owing to its high specific heat capacity, water is used as a:

26. Consider the following pairs: (I) Day – Earth's rotation (II) Month – Moon's phases (III) Year – Moon's phases Which of the pairs given above is/are correctly matched?

27. An object is placed between the optical centre and the principal focus of a convex lens. The image formed is:

28. A car covers 45 km in the first hour, 55 km in the second hour and 35 km in the third hour. Its average speed is:

29. The change of state from solid to liquid is called:

30. The fourth planet in order of increasing distance from the Sun is: