Physics Chemistry & Biology Test
Deficiency of which of the following nutrients is the most common cause of goiters?
  • Iron
  • Vitamin C
Explanation: A goitre is an enlargement of the thyroid gland, which can cause swelling in the neck. It often results from iodine deficiency, as iodine is crucial for the production of thyroid hormones. When the body doesn't get enough iodine, the thyroid gland can become enlarged to try and compensate for the lack of hormones. The term "goitre" originates from the Latin word "gutturia," meaning throat.
Which one of the following parts of the human brain is the regulating centre for swallowing and vomiting?
  • Cerebrum
  • Cerebellum
  • Pons
  • Medulla Oblongata
Explanation: The medulla oblongata, located at the base of the brainstem, controls vital autonomic functions such as vomiting, hiccupping, swallowing, coughing, and sneezing. It plays a crucial role in maintaining basic physiological processes essential for survival, including regulating heart rate and breathing.
Which of the following does not increase when we move from left to right along a period in the periodic table?
  • Oxidising Power of elements
  • Electronegativity
  • Non-metallic Character
  • Reducing power
Explanation: When moving from left to right along a period in the periodic table: Oxidising Power of Elements: Increases because elements become more reactive as oxidizing agents. Electronegativity: Increases because atoms attract electrons more strongly. Non-metallic Character: Increases because elements become more non-metallic (more likely to gain electrons). Reducing Power: Decreases because elements become less likely to donate electrons as reducing agents.
What is the value of Triple point of water?
  • 273.16 K
  • 273.16° C
  • 0° C
  • -273.16 K
Explanation: The triple point of water is indeed 273.16 K. This is the temperature at which water can exist simultaneously in its solid, liquid, and gaseous states. The Kelvin scale is the SI unit for temperature, starting from absolute zero.
What is the relationship between the frequency and the pitch of a sound wave?
  • Higher the frequency, higher the pitch
  • Lower the frequency, higher the pitch
  • Pitch is not dependant on the frequency
  • None of the above
Explanation: The brain interprets the frequency of a sound wave as its pitch. Higher frequencies result in higher pitches because the vibrations occur more rapidly, which the auditory system perceives as a higher pitch. Conversely, lower frequencies produce lower pitches with slower vibrations.
What is meant by Atomic number of an atom?
  • total number of protons
  • total number of electrons in an uncharged atom
  • Both a and b
  • None
Explanation: The atomic number of an atom is defined as the total number of protons in its nucleus. In an uncharged atom, the number of electrons equals the number of protons, so the atomic number also represents the number of electrons. The atomic number, or proton number, indicates the number of protons in an atom's nucleus and, for uncharged atoms, also equals the number of electrons. This number uniquely identifies each element and determines its position in the periodic table.
Which of the following represents the Snell’s law?
  • sine of angle of incidence/sine of angle of refraction = constant
  • cosine of angle of incidence/cosine of angle of refraction = constant
  • tangent of angle of incidence/tangent of angle of refraction = constant
    • Explanation: Snell’s Law is represented by the equation: Sinθ1/sinθ2=v1/v2=constant where: • θ1 is the angle of incidence • θ2 is the angle of refraction • v1 and v2 are the velocities of light in the two media.