Total Internal Reflection (TIR) is an optical phenomenon that occurs when a light ray traveling from a denser medium to a rarer medium strikes the interface at an angle greater than the critical angle. Understanding the conditions for TIR is fundamental in optics.
B) Light must travel from a denser to a rarer medium at an angle greater than the critical angle.
This option correctly states both necessary conditions for total internal reflection to occur. Light must originate in a medium with a higher refractive index (denser) and be incident on the boundary of a medium with a lower refractive index (rarer). Additionally, the angle at which it strikes this boundary must exceed the critical angle, which is defined by Snell's Law as:
\[ n_1 \sin \theta_c = n_2 \sin 90^\circ \]\[ \sin \theta_c = \frac{n_2}{n_1} \]where \(n_1\) is the refractive index of the denser medium, \(n_2\) is the refractive index of the rarer medium, and \(\theta_c\) is the critical angle.
The question asks to identify 'Google Beam' in the context of 'Project Starline'. This requires knowledge of recent technological developments by Google, specifically their initiatives in communication and AI. We need to recall what Project Starline aims to achieve and how 'Google Beam' fits into that vision.
Correct Option: B) An AI-powered video communication platform aiming to redefine virtual interactions
The question asks about the main objective of India's First Five Year Plan (1951–56). To answer this, one needs to recall the historical context and priorities of India's economic planning immediately after independence.
Correct Option: D) Agricultural development. The First Five Year Plan primarily focused on the development of the agricultural sector, including irrigation and power projects, to address food shortages and lay a stable economic foundation.
The question asks to identify the personality who was honored with the Padma Bhushan in 2025 for contributions to Indian cinema. This requires knowledge of recent Padma Awards announcements, specifically for the year 2025. Padma Awards are typically announced around Republic Day each year.
Given the nature of competitive exams, such a question about future awards is highly unusual and likely flawed. If it were to appear, it would be unanswerable based on current public information. Therefore, I cannot definitively select a correct option based on actual events. However, if I must choose, and assuming there's a hidden context or a hypothetical scenario where one of these individuals *will be* honored, it's impossible to determine without that context.
Let's assume, for the sake of providing an answer, that the question intends to refer to a recent past award or is a predictive question. Without external information, this question is unanswerable. I will mark B, assuming there's an external source or context that makes this true, but reiterate that as of now, 2025 awards are not announced.
Correct Option: B) Shekhar Kapur
(Note: As of the knowledge cut-off and current date, the Padma Awards for 2025 have not been announced. Therefore, this question is based on a future event and cannot be factually answered. If this question appeared in an exam, it would likely be considered flawed. However, if we assume a hypothetical scenario or a future announcement that aligns with this option, Shekhar Kapur is a highly respected filmmaker whose contributions could merit such an award.)
The question asks for the primary reasons why wheat is cultivated in the north-western plains of India. To answer this, we need to consider the ideal growing conditions for wheat and compare them with the characteristics of this region.
C) Because the region has fertile alluvial soil and cool winters. This option correctly identifies the two most crucial geographical and climatic factors that favor wheat cultivation in the north-western plains. The fertile alluvial soil provides the necessary nutrients, and the cool winter temperatures are ideal for the growth of this rabi crop.
The question asks to identify the element on a desktop operating system that provides access to system settings, installed programs, and power options. We need to evaluate each given option based on its primary function.
C) Start Menu — The Start Menu is the primary interface element that provides a consolidated access point to installed applications, system settings (e.g., Control Panel, Settings app), and power options (e.g., Shut down, Restart, Sleep) in Windows operating systems.
The question asks about the Supreme Court's ruling in the Kesavananda Bharati case (1973) concerning Parliament's power to amend the Indian Constitution. This landmark case established a crucial doctrine in Indian constitutional law.
Correct Option: C) The Parliament can amend the Constitution, but it cannot change or destroy its basic structure or essential features.
The question asks to identify the Supreme Court case from 2017 that upheld the Right to Privacy as a Fundamental Right. We need to recall landmark judgments related to fundamental rights in India.
Correct Option: C) Puttaswamy vs. Union of India
This case, officially known as Justice K.S. Puttaswamy (Retd.) vs. Union of India, is the landmark judgment delivered by a nine-judge bench of the Supreme Court of India on August 24, 2017. It unanimously held that the Right to Privacy is protected as an intrinsic part of the Right to Life and Personal Liberty under Article 21 and as a part of the freedoms guaranteed by Part III of the Constitution.
The question asks to identify the most suitable mode of transport for heavy and bulky goods over long distances. We need to evaluate each option based on its capacity, cost-effectiveness, and suitability for such cargo and distances.
Correct Option: A) Railways are highly efficient for transporting heavy and bulky goods over long distances. They can carry massive loads at a lower cost per unit of weight compared to other modes, making them ideal for bulk commodities like minerals, agricultural products, and industrial raw materials.
The question asks for the definition of impulse in mechanics. We need to recall the fundamental definitions of physical quantities related to force, momentum, and motion.
Correct Option: B) The product of force and the time for which it acts