General Science — Physics — 30Q Speed Round

Question 1

SI unit of length is:‌​‍

Accepted Answer

Metre — Metre (m) is the SI unit of length.‌​‍

Answer

Centimetre

Answer

Kilometre

Answer

Mile

Question 2

Sphygmomanometer measures:‌​‍

Accepted Answer

Blood pressure — Sphygmomanometer (BP apparatus) measures blood pressure.‌​‍

Answer

Heart rate

Answer

Blood sugar

Answer

Lung capacity

Question 3

Sound cannot travel through:‌​‍

Accepted Answer

Vacuum — Sound needs a medium to travel. ‌​‍It cannot travel through vacuum (no molecules to vibrate).

Answer

Air

Answer

Water

Answer

Steel

Question 4

Nautical mile is used to measure:‌​‍

Accepted Answer

Sea/air distance — Nautical mile (~1.852 km) is used in maritime and aviation navigation.‌​‍

Answer

Land distance

Answer

Height

Answer

Depth

Question 5

Household wiring uses which circuit?‌​‍

Accepted Answer

Parallel — Parallel circuit — if one appliance fails, others keep working. ‌​‍Voltage remains same across all.

Answer

Series

Answer

Mixed

Answer

None

Question 6

LED stands for:‌​‍

Accepted Answer

Light Emitting Diode — LED = Light Emitting Diode. Energy-efficient lighting technology.‌​‍

Answer

Light Emitting Device

Answer

Laser Emitting Diode

Answer

Low Energy Display

Question 7

The lens used to correct myopia is:‌​‍

Accepted Answer

Concave — Myopia (short-sightedness) is corrected by concave (diverging) lens.‌​‍

Answer

Convex

Answer

Bifocal

Answer

Cylindrical

Question 8

Ultrasound has frequency above:‌​‍

Accepted Answer

20,000 Hz — Ultrasound = above 20,000 Hz (above human hearing range). ‌​‍Used in medical scans (sonography).

Answer

20 Hz

Answer

200 Hz

Answer

2,000 Hz

Question 9

The pH of pure water is:‌​‍

Accepted Answer

7 — Pure water has a pH of 7, which is neutral. ‌​‍Below 7 = acidic, above 7 = alkaline.

Answer

0

Answer

5

Answer

14

Question 10

Seismograph measures:‌​‍

Accepted Answer

Earthquakes — Seismograph records earthquake waves (seismic waves).‌​‍

Answer

Wind

Answer

Temperature

Answer

Pressure

Question 11

Dry ice is the solid form of:‌​‍

Accepted Answer

Carbon Dioxide — Dry ice is solid Carbon Dioxide (CO₂). ‌​‍It sublimes directly from solid to gas at -78.5°C, without passing through a liquid phase.

Answer

Oxygen

Answer

Nitrogen

Answer

Water

Question 12

One horsepower equals approximately:‌​‍

Accepted Answer

746 watts — 1 HP ≈ 746 watts. Used to measure engine power.‌​‍

Answer

546 watts

Answer

646 watts

Answer

846 watts

Question 13

Laughing gas is:‌​‍

Accepted Answer

Nitrous Oxide (N₂O) — Nitrous Oxide (N₂O) is called laughing gas. ‌​‍It is used as an anaesthetic in dentistry and surgery. It causes a feeling of euphoria when inhaled.

Answer

Carbon Monoxide (CO)

Answer

Carbon Dioxide (CO₂)

Answer

Nitric Oxide (NO)

Question 14

The unit of frequency is:‌​‍

Accepted Answer

Hertz — Hertz (Hz) = unit of frequency (cycles per second). ‌​‍Decibel = unit of sound intensity.

Answer

Decibel

Answer

Watt

Answer

Newton

Question 15

Which metal is liquid at room temperature?‌​‍

Accepted Answer

Mercury — Mercury (Hg) is the only metal that is liquid at room temperature. ‌​‍Bromine is the only non-metal that is liquid at room temperature.

Answer

Lead

Answer

Zinc

Answer

Tin

Question 16

The mirror used as a rear-view mirror in vehicles is:‌​‍

Accepted Answer

Convex mirror — Convex mirrors are used as rear-view mirrors because they provide a wider field of view, allowing drivers to see more of the road behind.‌​‍

Answer

Plane mirror

Answer

Concave mirror

Answer

Parabolic mirror

Question 17

The unit of electrical resistance is:‌​‍

Accepted Answer

Ohm — Ohm (Ω) is the unit of electrical resistance. Named after Georg Ohm.‌​‍

Answer

Volt

Answer

Ampere

Answer

Watt

Question 18

A mirage is due to:‌​‍

Accepted Answer

Total internal reflection — Mirages are caused by total internal reflection of light in layers of hot air near the ground.‌​‍

Answer

Reflection

Answer

Dispersion

Answer

Diffraction

Question 19

Ohm's Law states that:‌​‍

Accepted Answer

V = IR — Ohm's Law: V = IR (Voltage = Current × Resistance). ‌​‍This is the fundamental law of electricity.

Answer

F = ma

Answer

E = mc²

Answer

P = VI

Question 20

Sound travels fastest in:‌​‍

Accepted Answer

Steel — Sound travels fastest in solids (steel ~5,960 m/s) > liquids (water ~1,480 m/s) > gases (air ~343 m/s). ‌​‍Sound cannot travel through vacuum.

Answer

Vacuum

Answer

Air

Answer

Water

Question 21

The fuse wire in an electrical circuit is made of:‌​‍

Accepted Answer

Lead-tin alloy — Fuse wire is made of lead-tin alloy with low melting point — melts and breaks circuit during overload.‌​‍

Answer

Copper

Answer

Silver

Answer

Gold

Question 22

White light splits into colours through a prism. This is called:‌​‍

Accepted Answer

Dispersion — Dispersion = splitting of white light into 7 colours (VIBGYOR) by a prism.‌​‍

Answer

Reflection

Answer

Refraction

Answer

Diffraction

Question 23

Rusting of iron is a process of:‌​‍

Accepted Answer

Oxidation — Rusting is oxidation of iron: Iron + Oxygen + Moisture → Iron Oxide (rust/Fe₂O₃). ‌​‍It requires both oxygen and water.

Answer

Reduction

Answer

Sublimation

Answer

Fermentation

Question 24

Ohm's Law states:‌​‍

Accepted Answer

V = IR — Ohm's Law: Voltage = Current × Resistance (V = IR).‌​‍

Answer

F = ma

Answer

E = mc²

Answer

PV = nRT

Question 25

Barometer measures:‌​‍

Accepted Answer

Atmospheric pressure — Barometer measures atmospheric pressure. Invented by Torricelli.‌​‍

Answer

Temperature

Answer

Humidity

Answer

Altitude

General Science — Physics — 30Q Speed Round