Level 1
Physical Science MCQs set 2 for Pakistan Coast Guard / Maritime Security Everyday Science — 20 solved questions.
Q1. One thousand watts of power is called:
Answer: 1.0 kilowatt
Explanation: By SI definition, 1 kilowatt (kW) equals exactly 1,000 watts; so 1,000 W = 1.0 kW.
Q2. What are the primary colors of light?
Answer: Red, blue, green
Explanation: The three primary colors of light (additive color model) are red, green, and blue (RGB); combining all three at full intensity produces white light.
Q3. The exchange of carbon dioxide and oxygen gas between the cell and the atmosphere during photosynthesis takes place by:
Answer: Diffusion
Explanation: Gases (CO₂ and O₂) move between cells and the atmosphere by simple diffusion - moving passively from areas of higher concentration to lower concentration without energy expenditure.
Q4. Four identical kettles with the same amount of water have bases made of different metals of the same thickness. If these are placed on identical flames, water will boil first in the kettle with a base made of:
Answer: Copper
Explanation: Copper has the highest thermal conductivity (about 401 W/m·K) among the options, so it transfers heat from the flame to the water most rapidly, bringing it to boil first.
Q5. A plant with green leaves placed in red light will appear:
Answer: Black
Explanation: Green leaves absorb red light (not reflecting it) for photosynthesis, so under red light the leaves appear black because they absorb the red light and have no other color to reflect.
Q6. In the periodic table, on moving from left to right across a period, the metallic character of an element:
Answer: Decreases
Explanation: Across a period from left to right, nuclear charge increases, pulling electrons closer and reducing atomic radius; this trend increases ionization energy and decreases metallic character.
Q7. A device which converts chemical energy into electrical energy is called a ____.
Answer: Battery
Explanation: A battery converts chemical energy into electrical energy through electrochemical redox reactions between its electrodes and electrolyte.
Q8. What is the SI unit of heat?
Answer: Joule
Explanation: In the SI system, the joule (J) is the standard unit of energy, including heat energy; one joule equals one Newton-meter or one watt-second.
Q9. A study of the chemical composition of the Earth's crust is called:
Answer: Geology
Explanation: Geology encompasses the study of Earth's composition, structure, and processes, including the chemical makeup of the crust through its sub-discipline geochemistry.
Q10. The rocks formed out of layers of sediment bonded together are known as:
Answer: Sedimentary rocks
Explanation: Sedimentary rocks is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q11. A light-year measures what?
Answer: Distance
Explanation: A light-year is a unit of distance - the distance light travels in one year (approximately 9.46 × 10¹² km) - not a unit of time despite containing the word "year."
Q12. Which chemical element has properties of both a metal and a non-metal?
Answer: Metalloid
Explanation: Metalloids (e.g., silicon, germanium, arsenic) exhibit properties intermediate between metals and non-metals, such as semiconductivity, making them useful in electronics.
Q13. All forms of energy that we use are ultimately transformed into:
Answer: Heat energy
Explanation: By the second law of thermodynamics, all energy conversions ultimately produce heat as a byproduct; heat is the final, degraded form into which all useful energy is eventually transformed.
Q14. Cu is the symbol of which element of the Periodic Table?
Answer: Copper
Explanation: Copper is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q15. Einstein's famous equation, which states that mass and energy are interchangeable, is:
Answer: E = mc²
Explanation: Einstein's mass-energy equivalence equation E = mc² states that energy equals mass multiplied by the square of the speed of light, showing mass and energy are interchangeable.
Q16. One kilowatt-hour is the amount of electrical energy that is consumed by a 1000-watt appliance in:
Answer: 1 hour
Explanation: One kilowatt-hour equals the energy consumed by a 1000-watt (1 kW) device operating for exactly 1 hour; by definition, Power × Time = 1 kW × 1 h = 1 kWh.
Q17. Analytical solutions to quadratic equations were introduced by ______.
Answer: Al-Khwarizmi
Explanation: Al-Khwarizmi, the 9th-century Persian mathematician, systematically presented methods for solving quadratic equations in his foundational work "Al-Kitab al-mukhtasar fi hisab al-jabr wal-muqabala."
Q18. What are the vertical columns in the Periodic Table called?
Answer: Groups
Explanation: In the Periodic Table, vertical columns are called Groups (or families), which contain elements with similar chemical properties and the same number of valence electrons.
Q19. Which among the following types of lenses are prescribed by doctors for a patient suffering from astigmatism?
Answer: Cylindrical lens
Explanation: Astigmatism results from an irregularly shaped cornea or lens; cylindrical (toric) lenses compensate by refracting light differently in different meridians to correct the uneven curvature.
Q20. Which instrument is used to measure the power of an electric circuit?
Answer: Wattmeter
Explanation: Wattmeter is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.