50 Science Quiz Questions and Answers
This page lists 50 real questions from the Quizlino Science category, each with four options, the correct answer and, where available, a short explanation. They are arranged from easy to hard, so you can start at the level that suits you. The full category contains 263 questions spread across its levels, so what you see here is a sample to study from, not the whole quiz.
- Cover the answer line, read the question and decide on your option first.
- Check the answer, then read the explanation even if you were right.
- Make a note of the questions you missed and come back to them after a few days.
- When you feel ready, play the timed Science to test yourself properly.
Science: Easy Questions
Warm-up questions that most players can answer.
Q1. What travels faster, light or sound?
Answer: A. Light
Explanation: Light is much faster than sound.
Q2. Which instrument is used to measure temperature?
Answer: B. Thermometer
Explanation: A thermometer measures temperature.
Q3. What state of matter is water vapor?
Answer: C. Gas
Explanation: Water vapor is gaseous.
Q4. What state of matter is ice?
Answer: A. Solid
Explanation: Ice is solid water.
Q5. What state of matter is liquid water?
Answer: B. Liquid
Explanation: Water is liquid at room temperature.
Q6. Which is the largest planet in our solar system?
Answer: B. Jupiter
Explanation: Jupiter is the largest planet.
Q7. Which planet is closest to the Sun?
Answer: C. Mercury
Explanation: Mercury is the closest planet.
Q8. Which organ removes waste from the blood?
Answer: C. Kidneys
Explanation: Kidneys filter waste from blood.
Q9. Which organ is used for breathing?
Answer: C. Lungs
Explanation: Lungs are used for respiration.
Q10. Which is the largest organ of the human body?
Answer: C. Skin
Explanation: Skin is the largest organ.
Q11. How many teeth does an adult human typically have?
Answer: C. 32
Explanation: Adults typically have 32 teeth.
Q12. What is the center of an atom called?
Answer: C. Nucleus
Explanation: The nucleus is the center.
Q13. Which gas is most abundant in Earth's atmosphere?
Answer: C. Nitrogen
Explanation: Nitrogen makes up 78% of air.
Q14. What force resists motion between two contacting surfaces?
Answer: C. Friction
Explanation: Friction opposes relative motion.
Q15. Which part of the plant absorbs water?
Answer: C. Roots
Explanation: Roots absorb water from soil.
Q16. What is the green pigment in plants called?
Answer: A. Chlorophyll
Explanation: Chlorophyll absorbs light energy.
Q17. What is the chemical symbol for Oxygen?
Answer: A. O
Explanation: O is the chemical symbol.
Q18. How does light travel?
Answer: C. In straight lines
Explanation: Light travels in straight lines.
Q19. Sound cannot travel through which of the following?
Answer: D. Vacuum
Explanation: Sound requires a medium to travel.
Science: Medium Questions
A step up in difficulty, for players who know the basics.
Q20. How many bones are there in the adult human body?
Answer: A. 206
Explanation: The correct answer is 206.
Q21. Which type of blood vessel carries blood away from the heart?
Answer: A. Arteries
Explanation: The correct answer is Arteries.
Q22. Which type of blood vessel carries blood back to the heart?
Answer: D. Veins
Explanation: The correct answer is Veins.
Q23. Which part of the human eye controls the amount of light that enters?
Answer: B. Iris
Explanation: The correct answer is Iris.
Q24. Which part of the human eye is light-sensitive and acts like a camera screen?
Answer: C. Retina
Explanation: The correct answer is Retina.
Q25. Which gas is known as laughing gas?
Answer: B. Nitrous Oxide
Explanation: The correct answer is Nitrous Oxide.
Q26. Which gas is commonly used in balloons to make them float?
Answer: B. Helium
Explanation: The correct answer is Helium.
Q27. Which metal is the best conductor of electricity?
Answer: A. Silver
Explanation: The correct answer is Silver.
Q28. Which metal is the second best conductor of electricity and widely used in wiring?
Answer: C. Copper
Explanation: The correct answer is Copper.
Q29. What is the main source of energy for the Earth?
Answer: A. Sun
Explanation: The correct answer is Sun.
Q30. Which vitamin is important for blood clotting?
Answer: C. Vitamin K
Explanation: The correct answer is Vitamin K.
Q31. What is the name of the process by which plants make their own food?
Answer: C. Photosynthesis
Explanation: The correct answer is Photosynthesis.
Q32. Which gas do humans inhale for survival?
Answer: B. Oxygen
Explanation: The correct answer is Oxygen.
Q33. Which gas do humans exhale as a waste product of respiration?
Answer: A. Carbon Dioxide
Explanation: The correct answer is Carbon Dioxide.
Q34. What is the main gas found in natural gas?
Answer: D. Methane
Explanation: The correct answer is Methane.
Q35. What type of mirror is used as a rearview mirror in vehicles?
Answer: B. Convex
Explanation: The correct answer is Convex.
Q36. What type of lens is used in magnifying glasses?
Answer: D. Convex
Explanation: The correct answer is Convex.
Q37. Which vitamin is produced in the human body when exposed to sunlight?
Answer: A. Vitamin D
Explanation: The correct answer is Vitamin D.
Science: Hard Questions
Challenging questions for confident players.
Q38. Who formulated the three laws of motion?
Answer: C. Sir Isaac Newton
Explanation: Isaac Newton set out the three laws of motion in his book Principia, published in 1687.
Q39. What is the unit of electrical resistance?
Answer: B. Ohm
Explanation: Electrical resistance is measured in ohms, named after the German physicist Georg Ohm.
Q40. What type of energy does a moving object have?
Answer: C. Kinetic Energy
Explanation: Kinetic energy is the energy an object has because of its motion, and it increases with both mass and speed.
Q41. What do we call the energy stored in an object due to its position?
Answer: B. Potential Energy
Explanation: Potential energy is stored energy, such as that of water held behind a dam or a stretched spring.
Q42. What is the unit of force named after a famous scientist?
Answer: B. Newton
Explanation: The newton is the SI unit of force, named after Isaac Newton. One newton accelerates one kilogram by one metre per second squared.
Q43. What type of wave does not require a medium to travel?
Answer: C. Electromagnetic Wave
Explanation: Electromagnetic waves, such as light and radio waves, can travel through empty space, which is how sunlight reaches the Earth.
Q44. What is the name of the phenomenon where light bends as it passes through different mediums?
Answer: B. Refraction
Explanation: Refraction is the bending of light as it changes speed between materials, which is why a straw looks bent in a glass of water.
Q45. What is the unit of power?
Answer: B. Watt
Explanation: Power is the rate of doing work and is measured in watts, named after the engineer James Watt.
Q46. What do we call the bouncing back of light from a surface?
Answer: A. Reflection
Explanation: Reflection is the bouncing of light off a surface, and it is what allows us to see our image in a mirror.
Q47. What is the SI unit of temperature?
Answer: C. Kelvin
Explanation: The kelvin is the SI unit of temperature. Zero kelvin is absolute zero, the lowest temperature possible.
Q48. Which colour has the longest wavelength in the visible spectrum?
Answer: C. Red
Explanation: Red light has the longest wavelength of the visible colours, at around 700 nanometres, and violet has the shortest.
Q49. What is the principle that states energy cannot be created or destroyed?
Answer: B. Law of Conservation of Energy
Explanation: The law of conservation of energy says energy can only change from one form to another, so the total amount stays the same.
Q50. What type of lens is used to correct short-sightedness?
Answer: B. Concave Lens
Explanation: A concave lens spreads light rays outward, moving the focus back onto the retina for people with short sight.
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