REASONING AND LOGICAL TYPE QUESTIONS OF PHYSICS

Physics questions REASONING:-------

1. Small insects and spider can walk on water because of surface tension.
2. lightning is not due to the collision of clouds but it is due to the potential difference between the Earth surface and cloud surface.
3. It is the potential difference between the two points which allow the current to flow.if potential difference is zero then no current flows what ever may be the amount of potential between the two conductors. So bird sitting on the High tension cable of about 1100 volt never shocked with current because both bird and High tension lines are at the same potential so no current flows through the bird and hence bird do not die.
4. We can walk on the ground because of friction.
5. Water drops when sprinkled on the surface appear more cooler than the water splash. It is because when water splash breaks into two small drops of water exothermic reaction take place.
6. Bernoulli's theorem is one of the theorem which says total pressure energy kinetic energy and potential energy of a fluid remain constant. Lifting of aeroplanes can be explained by using bernoulli's theorem.
7. No force is required if acceleration of the system becomes zero.
8. When acceleration of the system becomes zero then velocity of the body is either 0 or constant.
9. Newton first law of motion explain the quality of the force. It mean what a force can do when it is applied to a body. Function of force is to provide acceleration. A body can never be accelerated without force.It mean force causes acceleration in the body.
10. Newton's second law of motion explain quantitative approach of the force.explain how much force is required to generate a particular acceleration.
11. When a planet comes near to the sun its orbital speed increases but when it is going away from the sun its speed decreases. However angular speed of the planet remain constant throughout the year.
12. When a person carrying spring balance with weight attached to it jump then he observe no reading in the spring balance that mean weight of the object become zero during free fall however mass of the body object remain same.
13. Weight of the person or any other object become zero at the centre of the earth however its mass remains same
14. When a person go to the moon its weight become one fifth as compared to earth but its mass remain constant
15. Satellite which are revolving around the earth if gain speed more than under root 2 x the orbital velocity then the escape forever from the Earth
16. Human eye has convex lens.
17. Human eye has lens of 576 megapixel.
18. Rainbows are formed by the the phenomenon of total internal reflection refraction of light and dispersion of light.
19. Diamond has maximum refractive index which is equal to 2.4
20. Diamond brilliance the most because when a Ray of light enter in the diamond it remain for larger time in it because of multiple time ti r
21. Cooking induction based on the fact that magnetic flux causes Eddy currents in the cooking utensil which produces heat.
22. Electromagnetic waves are microwaves in the mobile phone generated when an electron oscillate in a diode. these oscillation produces electromagnetic waves. When electron gain sudden speed its mass increases and it immediately gets deacclerted due to which it radiate electromagnetic radiation, this is the cause of electromagnetic radiations which are emerging from the mobile phone
23. Clouds appear white because they reflect all the colours equally.
24. Sky appears blue because blue colour scatter maximum among all the colours so when sunlight enter towards the earth atmosphere then blue light gets scattered in the sky while all the colours and in the earth atmosphere.
25. Always red colour is used as danger signal this is because red colour scatter less and therefore it propagate in a straight line and can be visible from larger distance.
26. Current always flows in a less registry path if two resistances are connected to a current carrying conductor then the resistance which is less has more amount of current flowing in it.
27. Light year is the unit of distance. It is the time taken by the light to travel in one complete Earth year.
28. Light can makes 17 rounds around the earth in one second
29. Sunlight takes about 8 minutes to reach the surface of Earth.
30. We see the Sun 8 minutes past we cannot see the present sun.
31. Many stars are billion light years away from us so if there light enters in our eye so that mean we are looking their past which was billion light years back.
32. Displacement is always less than or equal to the distance
33. Average speed can never be 0 but average velocity can be zero.
34. If a swimmer want to cross the river in minimum distance then he has to dive by making an angle theta with the width of the river. And similarly if there was two cross the river in minimum time he has to dive perpendicular to the direction of the flow of water. Remember here all the directions are opposite to the flow of water
35. Scalar quantities has only magnitude.why vector quantity possesses both magnitude as well as direction.
36. Polar vector are those which gives linear effect for example velocity force acceleration
37. axial vector are those vector which gives rotational effect for example torque angular momentum and angular velocity
38. Dot Product of two mutually perpendicular vectors are always zero
39. Cross product of two parallel vector is always zero
40. Tensor of rank zero is called scalar product while tensor of rank 1 are vector product
41. If a particle is thrown vertically upward it attained zero range
42. Range of a projectile is maximum if its if it is thrown at an angle 45 degree to the ground
43. total mechanical energy of the projectile remain conserved at every point of its motion
44. Range of projectile is same as to angle theta and theta minus 90 degree
45. Inertia is that property of a metal by virtue of which it cannot change its direction of motion speed change of state by itself.
46. Rockets works on the principle of conservation of linear momentum
47. When a gun recoil it follows law of conservation of linear momentum
48. When lift move upward and a person is standing on a weighing machine then its weight measured by the machine will be more than the lift at rest
49. When lift moves downward and a person is standing on a weighing machine then your weight will be less
50. If lift fall freely then person measure 058 and this is called weightlessness
51. When a man climbing the rope in the upward direction then tension in the rope increases and vice versa
52. It is not always true that friction opposes the motion but in many cases it IT act in the direction of motion for example rolling of a tyre aur a ring.
53. When a person carrying weight on his head and moving parallel to the ground then he does zero work
54. A person pulling rope full of bucket from a well then she does positive work
55. Horse pulling a cart is an example of positive work
56. Work done by gravitational force when a ball is thrown upward is negative work and vice versa
57. work done by frictional forces viscous forces and drag forces are always negative
58. Gravitational force is an example of conservative force. Work done under these forces are always 0 for complete path
59. Power dissipated by the conservative forces is always zero
60. When is spring is correct it possesses potential energy and when it is released this potential energy converted into kinetic energy
61. Potential energy of conservative forces are the negative line integral of the conservative force.
62. When pendulum oscillates it has maximum kinetic energy at the mean position and kinetic energy at the extreme positions
63. Pendulum has maximum potential energy at the extreme positions
64. When brakes are applied to the car then stopping distance depends upon the kinetic energy and the stopping force
65. Collision between the two bodies is always follows laws of conservation of linear momentum whatever may be the type of collision.
66. In case of perfectly elastic collision energy is always conserved but for inelastic collision and for perfectly inelastic collision kinetic energy is not conserved. However in all the three type of origin momentum is always conserved
67. Collision between the subatomic atomic particle can also be considered as the change in the path of the particle
68. When light body collide with the heavier body elastically then have your body remain at rest but lighter body rebound back with the same velocity
69. When two bodies of equal masses and equal velocities moving opposite to each other and collide elastically then both retraces their ordinal path after collision
70. When two bodies of equal masses collide in such a way that one of the mass is at rest then both the body's interchange their Kinetic energies
71. Radius of gyration has the same unit as that of distance
72. When a body rotate in a circular motion with a uniform speed then it has acceleration which is called centripetal acceleration and this acceleration is due to the change of direction of the body at every point
73. all the planets revolve around the sun in an elliptical orbits conserving angular momentum
74. When planet is close to sun it has less moment of inertia due to which its orbital velocity increases to conserve angular momentum L=Iw.
75. A body moving along a vertical circle has minimum velocity required at the highest point is given by under root gr.
76. Minimum velocity for a body to move in a vertical circle at the bottom is under root 5 gr
77. moment of inertia plays the same role in rotational motion as the mass in the linear motion
78. If two bodies rotating in a circular path concentric to each other with the same angular velocity then both possesses same time period.
79. gravitational force is always and attractive force and it acts along the line joining the centre of the two masses it is also called long-range force
80. Gravitational force is weaker then electric forces and nuclear forces
81. When a body is taken to a height h from the surface of Earth then value of g act on it decreases and if the same body is taken inside Earth then again value of g decreases.
82. For the same decrease in the value of g with height and depth it is calculated that value of of depth required is 2 time the height to which the body is taken above the surface of Earth
83. Value of g at equator is less than at pole because equator radius is 21 kilometre larger than the polar radius.
84. if Earth rotates 17 times the present speed then value of g becomes zero and all the bodies on the surface of Earth flying in the air
85. Weight of the body at equator is less than at pole
86. For the same kilogram weight of sugar at equator and pole you will get more sugar at equator
87. Escape velocity of a body does not depend upon its mass how it depends upon the mass of the planet and its radius
88. Escape velocity on the surface of Earth is 11.2 kilometre per second
89. Escape velocity on the surface of moon is 2.31 km per second
90. Kepler's second law is based on law of conservation of angular momentum
91. Breaking force is directly proportional to area of cross section and breaking stress is constant for a given material does not depend upon the dimensions of the wire that mean if two wires having different length and area of cross section the same breaking stress
92. Poison ratio is the ratio of the lateral strain to the longitudinal strain
93. Strain has no units but stress has same unit as that of pressure
94. Operation like annealing or any other  imprheat treatment improve the crystal structure and relieving the internal stresses and improve the strength of the material
95. breaking stress depends upon the nature of the material it does not depend upon the shape and size of the material
96. When rod is heated and both of its  rigidly supported then wire has compressive stresses and if heated rod which is supported from both the side by a rigid support is made to cool then tensile stresses are developed in the rod.
97. A pendulum clock run slower in summer and faster in the winter. It is because in summer length of the pendulum increases and its time period increases. There for time measured by the clock for the two events takes more time and hence it runs slow in summer
98. Gases exhibit two type of compressibility isothermal and adiabatic. Bulk modulus of elasticity is exhibited by solid liquids and gases.
99. Satellite revolving close to the earth has more angular velocity then the satellite who are away from the Earth
100. Geostationary satellites satellite which has their orbit in the equatorial plane of the earth