Showing 1–10 of 419 questions
Which of the following is NOT a renewable energy source?
A
Solar energy
B
Wind energy
C
Coal
D
Hydroelectric energy
Explanation:
Coal is a fossil fuel and non-renewable energy source. Solar, wind, and hydroelectric are all renewable sources.
What is the SI unit of electric current?
A
Volt
B
Ampere
C
Ohm
D
Watt
Correct Answer:
B. Ampere
Explanation:
Ampere (A) is the SI unit of electric current. Volt is for potential difference, Ohm for resistance, and Watt for power.
Which element has the atomic number 8?
A
Nitrogen
B
Oxygen
C
Carbon
D
Hydrogen
Correct Answer:
B. Oxygen
Explanation:
Oxygen has atomic number 8. It is essential for respiration in living organisms.
The speed of light in vacuum is approximately:
A
3 × 10^8 m/s
B
3 × 10^7 m/s
C
3 × 10^6 m/s
D
3 × 10^9 m/s
Correct Answer:
A. 3 × 10^8 m/s
Explanation:
The speed of light in vacuum is approximately 3 × 10^8 m/s or 299,792,458 m/s.
Which of the following is an example of a chemical change?
A
Melting of ice
B
Rusting of iron
C
Boiling of water
D
Dissolving salt in water
Correct Answer:
B. Rusting of iron
Explanation:
Rusting of iron is a chemical change as a new substance (iron oxide) is formed. Others are physical changes.
Q.6
Medium
General Science
What is the pH value of pure water at 25°C?
Explanation:
Pure water is neutral with a pH value of 7 at 25°C. Values below 7 are acidic and above 7 are basic.
Which planet is known as the Red Planet?
A
Venus
B
Mars
C
Jupiter
D
Saturn
Explanation:
Mars is called the Red Planet due to the presence of iron oxide (rust) on its surface.
The process by which plants make their own food using sunlight is called:
A
Respiration
B
Photosynthesis
C
Transpiration
D
Fermentation
Correct Answer:
B. Photosynthesis
Explanation:
Photosynthesis is the process where plants convert sunlight, water, and CO2 into glucose and oxygen.
Q.9
Medium
General Science
How many bones are there in the adult human body?
Explanation:
An adult human body has 206 bones. Infants are born with approximately 270 bones, many of which are cartilage.
Q.10
Medium
General Science
Which gas is primarily responsible for global warming?
A
Nitrogen
B
Oxygen
C
Carbon dioxide
D
Hydrogen
Correct Answer:
C. Carbon dioxide
Explanation:
Carbon dioxide (CO2) is the primary greenhouse gas responsible for global warming, released mainly through fossil fuel combustion.
