Which planet is known as the Red Planet?
A Venus
B Mars
C Jupiter
D Saturn
Mars appears red due to the presence of iron oxide (rust) on its surface.
What is the chemical formula of water?
A H₂O
B CO₂
C NaCl
D H₂SO₄
Water is composed of two hydrogen atoms and one oxygen atom.
Which gas is most abundant in the Earth’s atmosphere?
A Oxygen
B Carbon dioxide
C Nitrogen
D Hydrogen
About 78% of the Earth’s atmosphere consists of nitrogen.
Who proposed the law of gravitation?
A Albert Einstein
B Isaac Newton
C Galileo Galilei
D Johannes Kepler
Newton formulated the law of universal gravitation explaining the attraction between masses.
What is the unit of electric current?
A Ohm
B Watt
C Volt
D Ampere
Ampere is the SI unit used to measure the flow of electric current.
Which part of the human brain controls balance?
A Cerebrum
B Medulla
C Cerebellum
D Pons
The cerebellum maintains posture, balance, and coordination of voluntary movements.
Which of the following is a non-metal that remains liquid at room temperature?
A Mercury
B Bromine
C Gallium
D Sodium
Bromine is the only non-metal that exists as a liquid at room temperature.
Which vitamin is produced in the human body when exposed to sunlight?
A Vitamin A
B Vitamin B
C Vitamin C
D Vitamin D
The skin synthesizes Vitamin D when exposed to ultraviolet rays from sunlight.
What is the main constituent of biogas?
A Methane
B Ethane
C Carbon monoxide
D Hydrogen
Biogas mainly contains methane (CH₄), which is responsible for its fuel value.
What is the hardest naturally occurring substance?
A Iron
B Diamond
C Quartz
D Graphite
Diamond, a crystalline form of carbon, is the hardest natural substance known.
Which blood group is known as the universal donor?
A A
B B
C AB
D O
People with blood group O negative can donate blood to individuals of any blood group.
Which part of the plant conducts food?
A Xylem
B Phloem
C Cambium
D Cortex
Phloem transports food produced in the leaves to other parts of the plant.
What does DNA stand for?
A Deoxyribonucleic Acid
B Deoxynitric Acid
C Dicarboxylic Nucleic Acid
D Deoxy Natural Acid
DNA carries the genetic instructions used in the growth and functioning of all organisms.
What is the main function of the ozone layer?
A Trap heat
B Reflect sunlight
C Absorb ultraviolet rays
D Produce oxygen
The ozone layer absorbs harmful UV radiation, protecting living organisms.
Which instrument is used to measure blood pressure?
A Thermometer
B Barometer
C Sphygmomanometer
D Hygrometer
A sphygmomanometer measures the pressure exerted by circulating blood on artery walls.
Which element is used in the filament of an electric bulb?
A Copper
B Tungsten
C Aluminium
D Iron
Tungsten has a very high melting point, making it suitable for bulb filaments.
Which organ purifies blood in the human body?
A Heart
B Liver
C Kidney
D Lungs
Kidneys filter waste and excess substances from the blood to form urine.
Which device converts chemical energy into electrical energy?
A Generator
B Transformer
C Battery
D Motor
Batteries store chemical energy and convert it into electrical energy when in use.
Which is the largest organ in the human body?
A Liver
B Skin
C Heart
D Lungs
The skin covers the entire body surface and acts as a protective barrier.
Which gas is used for photosynthesis?
A Oxygen
B Carbon dioxide
C Nitrogen
D Hydrogen
Plants absorb carbon dioxide to produce glucose and oxygen through photosynthesis.
What type of mirror is used in vehicles as a rear-view mirror?
A Concave
B Plane
C Convex
D Cylindrical
Convex mirrors provide a wider field of view, enabling drivers to see more area behind.
What is the boiling point of water at sea level?
A 0°C
B 50°C
C 100°C
D 212°C
At standard atmospheric pressure, water boils at 100°C.
Which is the most reactive metal?
A Gold
B Potassium
C Iron
D Zinc
Potassium reacts vigorously with water and air, making it highly reactive.
What is the main function of red blood cells?
A Fighting infections
B Carrying oxygen
C Producing hormones
D Clotting blood
Red blood cells contain hemoglobin that transports oxygen to body tissues.
Which acid is present in lemon?
A Lactic acid
B Citric acid
C Oxalic acid
D Acetic acid
Lemons contain citric acid, responsible for their sour taste.