General Science - Physics MCQs
Physics Objective (Multiple Choice) General Knowledge & General Science Questions & Answers for SSC-CGL, UPPSC, NDA, CDS and all one day examinations of India. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
11. Sound velocity is usually larger in solids than in liquids and gases because:
[A] solids are more elastic than liquids and gases
[B] solids are less elastic than liquids and gases
[C] volumetric expansion coefficients of liquids and gases are higher than solids
[D] frequency of sound waves decreases in solids due to Doppler shift
Show Answer
Correct Answer: A [ solids are more elastic than liquids and gases]
Notes:
A substance is labelled more elastic if it offers greater resistance to deformation than other bodies, so that it can be stretched less than others.
12. Consider the following differences between White Gold and Yellow Gold:
- While White Gold has more Nickel, Yellow Gold usually contains more Zinc
- White Gold are more durable than Yellow Gold
Which of the above statements is/are correct?
[A] Only 1
[B] Only 2
[C] Both 1 & 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: B [ Only 2]
Notes:
First statement is incorrect because White Gold has more Zinc, whereas Yellow Gold usually contains more Nickel. White Gold has Rhodium coating, whereas Yellow Gold does not have the same. The Rhodium coating makes the White Gold costlier and more durable than Yellow Gold. White gold is an alloy of gold and at least one white metal, nickel, manganese or palladium.
13. Li-Fi (Light Fidelity):
- is a fast and cheap optical version of WiFi
- is based on LEDs for the transfer of data
- works only in direct line of sight
Which of the above statements is/are correct?
[A] Only 1 & 2
[B] Only 2 & 3
[C] Only 1 & 3
[D] 1, 2 & 3
Show Answer
Correct Answer: D [ 1, 2 & 3]
14. The magnetic lines of force:
1. are closed continuous curves
2. travel from north to south outside the magnet and from south to north inside the magnet
3. bend along the length of magnet
4. mutually repel each other
5. never intersect each other
Which among the above is / are correct?
[A] Only 1 & 2
[B] Only 1, 2 & 3
[C] Only 1, 2, 3 & 5
[D] 1, 2, 3, 4 & 5
Show Answer
Correct Answer: D [ 1, 2, 3, 4 & 5]
Notes:
Magnetic lines of force are closed continuous curves in a magnetic field along which the north pole will move if free to do so and its direction is given by the direction in which free north pole will point. The five points given in this questions are its notable properties.
15. When a body is in Uniform Circular Motion, there is no change in ___:
1. Speed
2. Amplitude
3. Velocity
4. Acceleration
Choose the correct option from the codes given below:
[A] Only 1
[B] Only 1 & 2
[C] Only 1, 2 & 3
[D] 1, 2, 3 & 4
Show Answer
Correct Answer: B [ Only 1 & 2]
Notes:
Uniform circular motion describes the motion of a body traversing a circular path at constant speed. The distance of the body from the axis of rotation remains constant at all times. Though the body’s speed is constant, its velocity is not constant: velocity, a vector quantity, depends on both the body’s speed and its direction of travel. This changing velocity indicates the presence of acceleration; this centripetal acceleration is of constant magnitude and directed at all times towards the axis of rotation. This acceleration is, in turn, produced by a centripetal force which is also constant in magnitude and directed towards the axis of rotation.
16. Who among the following is credited to work for the unification of electricity, magnetism and optics field of Physics?
[A] James Clerk Maxwell
[B] Michael Faraday
[C] Haris Christian Oersted
[D] Isaac Newton
Show Answer
Correct Answer: A [James Clerk Maxwell]
Notes:
James Clerk Maxwell made the efforts for the unification of electricity, magnetism and optics field of Physics. He showed that light is an electromagnetic wave. James Clerk Maxwell was a Scottish mathematician, physicist and is known best for his mathematical work on electromagnetism and on the behaviour of gases.
17. Optical Fibre technology works on which of these principles of Physics?
[A] Bernoulli’s Principle
[B] Newton’s law of Motion
[C] Total internal reflection of Light
[D] Photoelectric effect
Show Answer
Correct Answer: C [Total internal reflection of Light]
Notes:
Optical Fibre technology works on the principle of Total internal reflection of Light. It helps in transmitting light signals from one place to another with a negligible loss of energy, thereby enabling to carry more signals than copper cables.
18. Which of the following scientific discoveries was made by C.V Raman?
[A] Inelastic scattering of light by molecules
[B] Super Conductivity
[C] Controlled nuclear fission
[D] Cyclotron
Show Answer
Correct Answer: A [Inelastic scattering of light by molecules]
Notes:
C.V Raman discovered the Inelastic scattering of light by molecules in 1928, also named as ‘Raman effect’ Raman scattering is the inelastic scattering of a photon by molecules which are excited to higher vibrational or rotational energy levels. He was the first Indian Physicist to win the Nobel Prize for Physics in 1930. C.V Raman has also been bestowed with the Bharat Ratna Award.
19. 1 nautical mile is equivalent to which of the following?
[A] 1.44 x 1000 m
[B] 1.852 x 100 m
[C] 1.852 x 1000 m
[D] 1.44 x 100 m
Show Answer
Correct Answer: C [ 1.852 x 1000 m ]
Notes:nautical mile is a unit of length. 1 nautical mile is equal to 1.852 x 1000 m Other important units of length are:
- 1 mile = 1.609 x 1000 m
- 1 light year = 9.46 x 1015 m
- 1 AU = 1.5 x 1011m
- 1 Par sec = 3.1 x 1016m
20. What is the S.I unit of Pressure Energy?
[A] Nm
[B] Watt
[C] Joule
[D] No units
Show Answer
Correct Answer: C [ Joule ]
Notes:
Joule is the unit of Pressure energy. Pressure energy is the energy stored in a fluid due to the force per unit area applied onto it Pressure energy = Pressure x volume Its dimensional formula is M L2 T-2
