1. Consider the following statements:
- Both Plutonism and Volcanic Eruption involve cooling of Magma
- Both Plutonism and Volcanic Eruption involve bulk chemical changes
Which among the above statements is are correct ?
[A] 1 only
[B] 2 only
[C] Both 1 and 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: C [Both 1 and 2]
Notes:
Plutonism refers to the geological process of magma (molten rock) slowly cooling and solidifying beneath the Earth’s surface, forming intrusive igneous rocks such as granite. Volcanic eruptions occur when magma and ash are expelled from a volcano onto the Earth’s surface. They are caused by the release of pressure within the Earth’s mantle or crust. Plutonism and volcanic eruptions are both related to tectonic activity and can occur along plate boundaries or within the Earth’s mantle. Plutonism is a slow process that can take millions of years, while volcanic eruptions can happen suddenly and unpredictably.
2. Consider the following factors regarding a satellite maintaining its orbital position around the Earth:
- Distance from the Earth
- Tangential speed of the satellite
- Earth's radius
- Gravitational force of the Earth
- Mass of the satellite
- Size of the satellite
Which of the above determine the balance of centripetal force and gravitational attraction enabling stable orbit?
[A] Only 1, 2 and 3
[B] 1, 2, 3 and 6
[C] 1, 2, 3 and 4
[D] 1, 2, 3, 4, 5 and 6
Show Answer
Correct Answer: C [1, 2, 3 and 4]
Notes:
The stable orbital motion of a satellite is governed by the distance from the Earth, the tangential speed of the satellite, Earth's radius, and the gravitational force of the Earth. The mass and size of the satellite are not factors in this specific balance because gravitational and centripetal forces act proportionally to mass, and size is irrelevant to the orbital mechanics as per Newtonian gravitation.
3. Consider the following statements:
- The rotation of the Earth on its axis generates centrifugal force on water.
- The effect of centrifugal force in creating tides is of great use in determining the location of the high tides and low tides.
Which of the above statements is / are correct?
[A] Only 2
[B] Only 1
[C] Both 1 and 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: B [Only 1]
Notes:
The rotation of the Earth produces a centrifugal force on water, which is greatest at the equator. However, this force acts uniformly along a latitude and does not affect the determination of the locations of high and low tides. Hence, only the first statement is correct; the second statement is not factually valid.
4. Consider the following rocks:
- Pumice
- Basalt
- Granite
Which of the above is/are extrusive igneous rock(s)?
[A] 1 Only
[B] 2 & 3 Only
[C] 1 & 2 Only
[D] 3 Only
Show Answer
Correct Answer: C [ 1 & 2 Only]
Notes:
Granite is an intrusive igneous rock. Pumice and Basalt are extrusive igneous rocks. Igneous rocks are formed from cooling and solidification of magma. If the magma cools below the surface of earth’s surface, it is called intrusive igneous rock. If the magma cools above the surface of earth, it is called extrusive igneous rock.
5. Consider the following differences between Spring tides & Neap tides:
- While spring tides occur during full moon and new moon, neap tides occur during quarter moons
- While Spring tides occur twice a month, neap tides occur four times in a month
Which of the above statements is/are correct?
[A] 1 Only
[B] 2 Only
[C] Both 1 & 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: A [1 Only]
Notes:
First statement is correct. Second statement is incorrect because Neap tides occur twice a month when the Sun and Moon are at right angles to the Earth. Also, Spring tides occur twice each lunar month during during the syzygies
6. Consider the following statements regarding the modes of heat transfer:
- In conduction, there is no actual movement of molecules, whereas in convection, heat is transferred by the actual movement of molecules.
- Transfer of heat by conduction generally occurs in solids, while transfer by convection occurs primarily in liquids and gases.
Which of the above statements is/are correct?
[A] Both 1 and 2
[B] Only 1
[C] Only 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: A [Both 1 and 2]
Notes:
Both statements are correct. Conduction occurs mainly in solids, transferring heat through direct molecular contact without actual movement of molecules. Convection, on the other hand, involves the bulk movement of fluid (liquid or gas) molecules, carrying energy from hotter to cooler regions. Thus, conduction and convection differ fundamentally in their mechanisms and typical occurrence.
7. Which of the following properties cease to exist (become zero) at absolute zero temperature (0 K) on the Kelvin scale?
- Oscillation of atoms and molecules
- Entropy
- Electrical resistance
Select the correct option from the codes given below:
[A] Only 1
[B] Only 1 & 2
[C] Only 2 & 3
[D] None of them
Show Answer
Correct Answer: D [None of them]
Notes:
At absolute zero, atomic oscillations persist at minimal quantum levels and do not become zero. Entropy remains nonzero due to quantum effects. Electrical resistance approaches zero in superconductors but usually does not vanish entirely because of defects and quantum fluctuations. Thus, none of these properties become strictly zero at 0 K.
8. With reference to the phenomenon of mirage, consider the following statements:
- The refractive index of hot air is greater than that of cold air.
- When light rays pass from hotter to cooler layers of air, they curve downward.
- The phenomenon of superior mirage is most commonly found in polar regions.
Select the correct answer using the codes given below:
[A] Only 1 & 2
[B] Only 2 & 3
[C] Only 1 & 3
[D] 1, 2 & 3
Show Answer
Correct Answer: B [Only 2 & 3]
Notes:
Cold air is denser and has a higher refractive index than hot air, making statement 1 incorrect. Light bends downward when passing from hotter to cooler layers (statement 2 correct). Superior mirages commonly occur in polar regions due to sharp temperature gradients near the surface (statement 3 correct).
9. With reference to sound waves, consider the following statements:
- The frequency determines the pitch of a sound, and the amplitude determines the intensity (or loudness).
- Frequency is proportional to amplitude.
Select the correct option from the codes given below:
[A] Only 1
[B] Only 2
[C] Both 1 & 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: A [Only 1]
Notes:
Frequency affects the pitch of a sound, while amplitude affects its loudness or intensity; the two properties are independent. Frequency and amplitude are not proportional. Thus, statement 1 is correct, while statement 2 is incorrect. Sound can have any combination of pitch and loudness independent of each other.
10. Consider the following factors affecting the speed of sound:
- Amplitude
- Wavelength
- Humidity
Which of the above does the speed of sound depend upon?
[A] Only 3
[B] Only 2 & 3
[C] 1, 2 & 3
[D] None
Show Answer
Correct Answer: A [Only 3]
Notes:
The speed of sound is independent of amplitude and wavelength; it primarily depends on the properties of the medium, notably humidity (presence of water vapor). Higher humidity increases the speed of sound as moist air is less dense than dry air. Thus, only option 3 (humidity) affects the speed of sound.
