Everyday Science MCQs Set 4 – 20 Important Science Questions - PrepWis

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Sunday, August 16, 2026

Everyday Science MCQs Set 4 – 20 Important Science Questions

Everyday Science MCQs – Set 4

Practice 20 important Everyday Science MCQs covering biology, chemistry, physics, human body, earth science, astronomy and environmental science. Click Show Correct Answer to reveal the answer with a short explanation.

1. Which part of a plant absorbs most of the water and minerals from the soil?

  • A. Stem
  • B. Leaves
  • C. Root hairs
  • D. Flowers
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Correct Answer: C. Root hairs
Root hairs greatly increase the surface area of roots and help absorb water and dissolved minerals from the soil.

2. Which organ produces insulin in the human body?

  • A. Liver
  • B. Pancreas
  • C. Stomach
  • D. Gallbladder
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Correct Answer: B. Pancreas
The pancreas produces insulin, a hormone that helps regulate the level of glucose in the blood.

3. Which part of the digestive system is the main site of nutrient absorption?

  • A. Stomach
  • B. Large intestine
  • C. Small intestine
  • D. Oesophagus
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Correct Answer: C. Small intestine
Most digested nutrients are absorbed through the walls of the small intestine into the bloodstream or lymphatic system.

4. Which mineral is essential for the formation of strong bones and teeth?

  • A. Calcium
  • B. Sodium
  • C. Potassium
  • D. Chlorine
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Correct Answer: A. Calcium
Calcium is an important mineral needed for the development and maintenance of bones and teeth.

5. Which vitamin is important for normal blood clotting?

  • A. Vitamin A
  • B. Vitamin C
  • C. Vitamin K
  • D. Vitamin E
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Correct Answer: C. Vitamin K
Vitamin K is required for the production of several proteins involved in normal blood clotting.

6. Which acid is present in the human stomach and helps digestion?

  • A. Sulfuric acid
  • B. Hydrochloric acid
  • C. Nitric acid
  • D. Acetic acid
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Correct Answer: B. Hydrochloric acid
Hydrochloric acid in the stomach creates a strongly acidic environment that helps digestion and activates certain digestive enzymes.

7. Which metal is liquid at ordinary room temperature?

  • A. Iron
  • B. Copper
  • C. Mercury
  • D. Aluminium
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Correct Answer: C. Mercury
Mercury is a metal that remains liquid at typical room temperatures because of its relatively low melting point.

8. What is the pH value of a neutral solution at 25°C?

  • A. 0
  • B. 5
  • C. 7
  • D. 14
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Correct Answer: C. 7
At 25°C, a neutral aqueous solution has a pH of 7, meaning the concentrations of hydrogen and hydroxide ions are equal.

9. Which gas is commonly used to fill balloons because it is lighter than air and non-flammable?

  • A. Oxygen
  • B. Helium
  • C. Carbon dioxide
  • D. Nitrogen
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Correct Answer: B. Helium
Helium is less dense than air and is non-flammable, making it suitable for filling balloons.

10. Which material is generally considered a good conductor of electricity?

  • A. Rubber
  • B. Glass
  • C. Copper
  • D. Plastic
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Correct Answer: C. Copper
Copper has high electrical conductivity and is widely used in electrical wires and cables.

11. What happens to the resistance of a metallic wire when its temperature generally increases?

  • A. It decreases
  • B. It increases
  • C. It becomes zero
  • D. It remains exactly unchanged
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Correct Answer: B. It increases
For most metallic conductors, electrical resistance increases as temperature rises because increased atomic vibrations hinder the movement of electrons.

12. Which device converts electrical energy into mechanical energy?

  • A. Electric motor
  • B. Battery
  • C. Generator
  • D. Transformer
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Correct Answer: A. Electric motor
An electric motor converts electrical energy into mechanical motion.

13. Which simple machine consists of a rigid bar that pivots around a fixed point?

  • A. Pulley
  • B. Lever
  • C. Screw
  • D. Wedge
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Correct Answer: B. Lever
A lever is a rigid bar that turns around a fixed point called a fulcrum to move or lift a load.

14. Which phenomenon causes a straw to appear bent when placed in a glass of water?

  • A. Reflection
  • B. Diffraction
  • C. Refraction
  • D. Dispersion
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Correct Answer: C. Refraction
Refraction is the bending of light as it passes from one transparent medium into another with a different optical density.

15. Which instrument is used to record earthquake vibrations?

  • A. Barometer
  • B. Seismograph
  • C. Thermometer
  • D. Altimeter
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Correct Answer: B. Seismograph
A seismograph detects and records ground movements produced by earthquakes and other seismic events.

16. What is the process by which liquid water changes into water vapour?

  • A. Condensation
  • B. Freezing
  • C. Evaporation
  • D. Sublimation
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Correct Answer: C. Evaporation
Evaporation is the process in which liquid water changes into water vapour, usually from the surface of the liquid.

17. Which planet is known for having the Great Red Spot?

  • A. Saturn
  • B. Jupiter
  • C. Uranus
  • D. Neptune
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Correct Answer: B. Jupiter
Jupiter's Great Red Spot is a huge, long-lasting atmospheric storm located in the planet's southern hemisphere.

18. What causes day and night on Earth?

  • A. Earth's revolution around the Sun
  • B. The Moon's revolution around Earth
  • C. Earth's rotation on its axis
  • D. Changes in the Earth's distance from the Sun
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Correct Answer: C. Earth's rotation on its axis
Earth rotates on its axis, causing different parts of the planet to face toward or away from the Sun and producing day and night.

19. Which renewable energy source uses moving air to generate electricity?

  • A. Solar energy
  • B. Wind energy
  • C. Geothermal energy
  • D. Tidal energy
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Correct Answer: B. Wind energy
Wind turbines convert the kinetic energy of moving air into electrical energy.

20. Which layer of soil is generally richest in organic matter and supports much plant growth?

  • A. Topsoil
  • B. Bedrock
  • C. Parent rock
  • D. Core layer
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Correct Answer: A. Topsoil
Topsoil is the upper layer of soil and usually contains a high amount of organic matter, minerals and living organisms that support plant growth.

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