1. What will be the load experienced for a man with a load jumps from a high building?
A. Zero, because while falling, both the man and the load are falling at the same acceleration i.e. acceleration due to gravity.
2. Why does a ball bounce upon falling?
A. When a ball falls, it is temporarily deformed. Because of elasticity, the ball tends to regain its original shape for which it presses the ground and bounces up (Newton's Third Law of Motion).
3. Why is standing in boats or double decker buses not allowed, particularly in the upper deck of buses?
A. On tilting the centre of gravity of the boat or bus is lowered and it is likely to overturn.
4. Which is more elastic, rubber or steel?
A. Steel is more elastic for the same stress produced compared with rubber.
5. Which one would fall faster among a feather, a wooden ball and a steel ball fall simultaneously in a vacuum?
A. All will fall at the same speed in vacuum because there will be no air resistance and the earth?s gravity will exert a similar gravitational pull on all.
6. When a man fires a gun, he is pushed back slightly. Why?
A. As the bullet leaves the nozzle of the gun?s barrel with momentum in a forward direction, as per Newton's Third Law of Motion, the ejection imparts to the gun as equal momentum in a backward direction.
7. A man with a load jumps from a high building. What will be the load experienced by him?
A. Zero, because while falling, both the man and the load are falling at the same acceleration i.e. acceleration due to gravity.
8. If a feather, a wooden ball and a steel ball fall simultaneously in a vacuum, which one of these would fall faster?
A. All will fall at the same speed in vacuum because there will be no air resistance and the earth?s gravity will exert a similar gravitational pull on all.
9. Why does a man fall forward when he jumps out of a running train or bus?
A. He is in motion while in the train or bus. When he jumps out, his feet comes to rest while touching the ground but his upper portion which is still in motion propels him forward.
10. Why is a compass used as an indicator of direction?
A. The magnetic needles of a compass under the influence f the earth?s magnetic field lie in a north-south direction. Hence, we can identify direction.
11. Curved rail tracks or curved roads are banked or raised on one side. Why?
A. Because a fast moving train or vehicle leans inwards while taking turn and the banked or raised track provides required centripetal force to enable it to move round the curve.
12. What is Physics?
A. The word 'Physics' comes from the Greek word 'phusis' meaning 'nature', introduced by the ancient scientist 'Aristotle'. Man has always been fascinated by nature. So, he questioned and sought answers for every phenomena nature could offer. The branch of science which is devoted to the study of nature and natural phenomena is called Physics. It is expected that all the events in nature take place according to some basic laws. Physics reveals these basic laws from day-to-day observations.
13. Name the scientist who proposed Doppler Effect?
A. Christian Doppler
14. Who discovered the laws of planetary motion?
A. Johannes Kepler
15. Who first proposed the concept of Atomic number?
A. Henry Moseley
16. Sound waves can travel in vacuum. True or false
A. FALSE
17. In a vacuum flask, silvering reduces the loss of heat by
A. radiation
18. The period of oscillation of a pendulum depends on
A. length of the spring
19. Theory of relativity was explained by
A. Albert Einstein
20. Name the scientist who proposed Doppler Effect
A. Christian Doppler
21. Name the scientist who proposed pH value
A. Sorenson
22. Who discovered the Law of Gravitation
A. Sir Isaac Newton
23. A person in a moving vehicle is thrown forward when the vehicle stops suddenly. Why?
A. When a moving vehicle stops suddenly, a passenger will tend to fall forward because the lower part of his body in contact with the seat comes to stop suddenly but the upper part of his body is still in motion sharing the movement of the train. So on account of inertia, the passenger falls forward.
24. What method of arranging elements into related groups was invented by Dimitri Mendeleyev?
A. The periodic table.
25. What physicist remarked: "God is subtle, but he is not malicious"?
A. Albert Einstein.
26. What M-word defines anything that occupies space?
A. Matter.
27. What do you call a substance containing only one kind of atom?
A. An element.
28. What teenager began studying physics after he noticed a chandelier swinging during a 1581 earthquake?
A. Galileo.
29. What elementary particle's antiparticle is the positron?
A. The electron.
30. What element comes last alphabetically?
A. Zirconium.
31. What American physicist pioneered the theory of "black holes" in 1939?
A. J. Robert Oppenheimer.
32. What's a charged atom, with unequal numbers of electrons and protons?
A. An Ion.
33. What theory of physics proposes that energy is not transferred continuously but in discrete amounts?
A. The quantum theory.
34. What element was converted to plutonium in the first nuclear reactors?
A. Uranium.
35. What acronyms for "Weakly Interacting Massive Particles " and "Massive Compact Halo Objects" do physicists use to explain dark matter?
A. Wimps and Machos.
36. What astronomical term gradually replaced the cumbersome "gravitationally completely collapsed object"?
A. Black Hole.
37. What did scientists build in a squash court under a football stadium at the University of Chicago in 1942?
A. nuclear reactor.
38. What's the atomic number of hydrogen?
A. One.
39. What element begins with the letter "k"?
A. Krypton.
40. What F-word is defined in physics as a "nuclear reaction in which nuclei combine to form more massive nuclei"?
A. Fusion.
41. What E-word was the first elementary particle to be discovered?
A. The electron.
42. What's defined as the distance between a lens and its focal point?
A. It's focal length.
43. What founding father was knocked unconscious while attempting to electrocute a turkey?
A. Benjamin Franklin.
44. What three terms are represented in Newton's second law of motion F = ma?
A. Force, mass, acceleration.
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