All Free Everyday Science MCQs with Answers

1501. A train goes past a railway station at a high speed. A young boy standing on the edge of the platform is likely to __________?

• A. Remain unaffected
• B. Fall away from the train
• C. Fall towards the train
• D. Fall away from or towards the train depending upon the speed

Explanation: Fast-moving air beside the train lowers the pressure there, while the air on the other side exerts relatively greater pressure. This unbalanced pressure can push the boy towards the train.

1502. Which one of the following sets of color combinations is added in color vision in TV'?

• A. Red, green and blue
• B. Orange, back and violet
• C. White. red and yellow
• D. Yellow, green and blue

Explanation: Television screens use additive colour mixing, in which red, green and blue light combine in different intensities to produce other colours. This differs from pigment mixing used with paints.

1503. A Fahrenheit thermometer indicates a temperature of ' 14°F. its corresponding reading on the Celsius scale will be _________?

• A. - 2O°C
• B. - 10°C
• C. + 10°C
• D. + 20°C

Explanation: Use Celsius = (Fahrenheit minus 32) × 5/9. Thus (14 - 32) × 5/9 = -10°C.

1504. Lead ball falls through water more slowly than through air because __________?

• A. The value of 'g' is less in water
• B. Density of air is less than that of water
• C. Of the viscous force in water
• D. Of The surface tension of water

Explanation: Water exerts greater viscous resistance on the falling ball than air does, opposing its motion more strongly. The value of gravitational acceleration is essentially the same in air and water.

1505. The rear view mirror of a motor vehicle is ________?

• A. Concave
• B. Plane
• C. Convex
• D. Biconcave

Explanation: A convex mirror gives a wider field of view, allowing the driver to see more of the road behind. It forms upright, diminished images, unlike a concave mirror in ordinary rear-view use.

1506. Bats can also fly in dark because they are capable of taking the help of _________?

• A. Ultraviolet Waves
• B. Ultrasonic Waves
• C. Electromagnetic Waves
• D. Special Retina

Explanation: Bats emit ultrasonic sounds and use the returning echoes to locate objects and prey, a process called echolocation. Ultrasonic waves have frequencies above the human hearing range.

1507. T.V. transmission cannot cover a very large area because

• A. the strength of T.V. waves is very limited
• B. picture cannot be transmitted clearly after a specific distance
• C. the shape of the earth is spherical
• D. the air is not a good conductor of light and sound/waves

Explanation: TV signals generally travel by line of sight, so the Earth's curved surface blocks them beyond the horizon. This is why transmitters, relay stations and satellites are used to extend coverage.

1508. An iceberg is floating in sea. How much of its mass will remain above the surface of water?

• A. One tenth
• B. One fifth
• C. One fourth
• D. One third

Explanation: An iceberg floats with roughly one-tenth of its volume, and approximately one-tenth of its mass, above seawater because ice is less dense than seawater. The remaining nine-tenths is submerged.

1509. The sun appears red at sunrise and sunset while it appears white at noon, because

• A. Of refraction
• B. It is cooler at sunrise and at sunset
• C. Of diffraction leading to red end of the spectrum reaching the earth.
• D. Of Scattering of light due to dust particles and air molecules.

Explanation: At sunrise and sunset, sunlight travels through a longer path in the atmosphere, so shorter blue wavelengths are scattered more and red light reaches the eye. At noon, the shorter atmospheric path makes the Sun appear nearly white.

1510. An astronaut inside a spacecraft is in a state of weightlessness. This implies that?

• A. The mass of the astronaut is reduced to zero
• B. Gravity inside the spacecraft ceases to act
• C. The astronaut is outside the influence of the earth's gravitational force
• D. The astronaut and the spacecraft are both in a free-failing state

Explanation: Weightlessness means the astronaut and spacecraft are falling together under gravity, so no supporting force is felt. Earth’s gravity still acts, and the astronaut’s mass does not become zero.