The physical quantity measured in kg·m/s² is Force. The SI unit of force is the Newton (N), which is defined as the force required to accelerate a mass of 1 kilogram by 1 meter per second squared. Mathematically, Force = Mass × Acceleration.

• Work: Measured in joules (N·m).
• Power: Measured in watts (J/s).
• Motion: Describes movement, not a measurable quantity in these units.

Explanation: A heavy stone appears lighter when immersed in water because of the upward pressure or buoyant force exerted by the water. This phenomenon is explained by Archimedes’ Principle, which states that a body immersed in a fluid experiences an upward force equal to the weight of the fluid displaced by it. The greater the volume of the object submerged, the greater the buoyant force acting on it. Hence, the stone seems lighter in water, even though its actual mass remains the same.

Explanation: A carnivore is an animal that primarily eats the flesh of other animals. The tiger (Panthera tigris) is a true carnivore and an apex predator in its ecosystem. It has sharp canines and retractable claws adapted for hunting and tearing flesh. Tigers play a vital role in maintaining the ecological balance by controlling herbivore populations in forests.

Explanation: Below the critical temperature, gases can be liquefied by applying pressure because the intermolecular forces of attraction between gas molecules become effective. These forces pull the molecules closer together, resulting in the formation of a liquid state.

Explanation: Cadmium (Cd) is a toxic heavy metal released from industrial waste, batteries, and mining processes. When it enters the food chain (especially through contaminated rice or water), it accumulates in the body and affects the kidneys, causing protein loss in urine and kidney failure. It is also associated with Itai-Itai disease in Japan, characterized by kidney damage and brittle bones.

Explanation: The time period of a simple pendulum is given by the formula T = 2π√(L/g), where L is the length of the pendulum and g is the acceleration due to gravity. Since the Moon’s gravity is about 1/6th of Earth’s, the value of g decreases, causing the time period to increase.

In medical terminology, USG stands for Ultrasonography. It is a diagnostic imaging technique that uses high-frequency sound waves to create images of internal organs, tissues, and developing fetuses. USG is commonly used in obstetrics, cardiology, and abdominal examinations as it is safe and non-invasive.

• Undersized gland: Not a recognized medical term.
• Unsegmented gonads: Incorrect and unrelated to imaging.
• None of the above: Incorrect as option B is correct.

Explanation: Dengue fever is caused by the Dengue virus, which belongs to the Flavivirus group. It is transmitted to humans through the bite of an infected Aedes aegypti mosquito. The virus multiplies in the blood and causes symptoms such as high fever, severe headache, joint and muscle pain, rashes, and low platelet count. In severe cases, it can lead to Dengue hemorrhagic fever or Dengue shock syndrome. Prevention includes controlling mosquito breeding and avoiding mosquito bites.

The Widal test is used to diagnose Typhoid fever, a bacterial infection caused by Salmonella typhi. The test detects the presence of agglutinating antibodies (O and H) in a patient’s serum against the antigens of the typhoid bacteria. It helps confirm infection during the second week of illness.

• Cholera: Diagnosed by stool culture for Vibrio cholerae.
• Tuberculosis: Detected using sputum test or Mantoux test.
• AIDS: Diagnosed through ELISA or Western blot test for HIV.