General Science
Q.21
Easy
What is the SI unit of electrical resistance?
A
Ohm
B
Ampere
C
Volt
D
Watt
Explanation:
The SI unit of electrical resistance is Ohm (Ω), named after Georg Simon Ohm.
Q.22
Easy
At what temperature does water boil at standard atmospheric pressure?
A
90°C
B
100°C
C
110°C
D
120°C
Explanation:
Water boils at 100°C (373.15 K) at standard atmospheric pressure of 1 atm.
Q.23
Easy
Which gas is essential for respiration in humans?
A
Nitrogen
B
Carbon dioxide
C
Oxygen
D
Hydrogen
Correct Answer:
C. Oxygen
Explanation:
Oxygen is essential for aerobic respiration in humans. It is used by mitochondria to produce ATP.
Q.24
Easy
What is the chemical formula of table salt?
A
KCl
B
NaCl
C
CaCl2
D
MgCl2
Explanation:
Table salt is sodium chloride (NaCl), composed of sodium and chlorine ions.
Q.25
Easy
Which organ in the human body is responsible for filtering blood and producing urine?
A
Liver
B
Pancreas
C
Kidney
D
Heart
Correct Answer:
C. Kidney
Explanation:
Kidneys filter waste products from the blood to produce urine. Each person typically has two kidneys.
Q.26
Easy
What is the acceleration due to gravity on Earth's surface?
A
8.8 m/s²
B
9.8 m/s²
C
10.8 m/s²
D
11.8 m/s²
Correct Answer:
B. 9.8 m/s²
Explanation:
The standard acceleration due to gravity at Earth's surface is approximately 9.8 m/s² or 10 m/s² for approximations.
Q.27
Medium
Which of the following is a scalar quantity?
A
Velocity
B
Acceleration
C
Distance
D
Displacement
Correct Answer:
C. Distance
Explanation:
Distance is a scalar quantity as it has only magnitude. Velocity, acceleration, and displacement are vectors as they have both magnitude and direction.
Q.28
Medium
What is the process by which plants make their own food using sunlight?
A
Respiration
B
Photosynthesis
C
Fermentation
D
Decomposition
Correct Answer:
B. Photosynthesis
Explanation:
Photosynthesis is the process where plants convert sunlight, water, and carbon dioxide into glucose and oxygen.
Q.29
Medium
Which metal is liquid at room temperature?
A
Iron
B
Mercury
C
Aluminum
D
Copper
Correct Answer:
B. Mercury
Explanation:
Mercury is the only metal that remains liquid at room temperature (25°C). Its melting point is -38.8°C.
Q.30
Medium
What is the speed of light in vacuum?
A
2 × 10⁸ m/s
B
3 × 10⁸ m/s
C
4 × 10⁸ m/s
D
5 × 10⁸ m/s
Correct Answer:
B. 3 × 10⁸ m/s
Explanation:
The speed of light in vacuum is approximately 3 × 10⁸ m/s or 299,792,458 m/s to be precise.
