Showing 61–80 of 273

Q61.Which of the following planets has the smallest diameters____?

Easy
A Mercury
B Marx
C Pluto
D Venus
Planets PPSC

Correct Answer: A

Mercury has the smallest diameter of any planet in the Solar System.

Q62.Which of the following was first to be discovered in the chromospheres of the sun?

Easy
A Krypton
B Xenon
C Neon
D Helium
Planets PPSC

Correct Answer: D

Helium was first discovered in the Sun's chromosphere in 1868 through spectral analysis, before being found on Earth.

Q63.Which of the followong spacecrsft enabled man to step on the moon first?

Easy
A Spuntnik I
B Luna II
C Vostok I
D Apollo XI
Planets PPSC

Correct Answer: D

Apollo 11 was the spacecraft mission that first landed humans (Neil Armstrong and Buzz Aldrin) on the Moon in 1969.

Q64.Which one is the world’s largest mangrove forest(s)?

Easy
A Changa Manga Forest
B Amazon Forest
C Sundarbans Forest
D None of the above
Planets PPSC

Correct Answer: C

The Sundarbans, spanning Bangladesh and India, is the world's largest mangrove forest.

Q65.Comets revolves around?

Easy
A The sun
B The Moon
C The Earth
D Venus
Planets PPSC

Correct Answer: A

Comets, like planets, revolve around the Sun in elliptical orbits.

Q66.‘Black holes’ refers to____?

Easy
A Holes occurring in heavenly bodies
B Bright spots on the sun
C Collapsing object of high density
D Collapsing object of low density
Planets PPSC

Correct Answer: C

A black hole is a region of space formed from a collapsed object so dense that its gravity prevents even light from escaping.

Q67.A pulsar is a rapidly spinning neutron star which emits:

Easy
A A blinding light when it aligns with the planets
B Radio waves detectable from Earth
C A gravitational pull which attracts high energy dust particles
D Enough energy to power itself indefinitely
Planets PPSC

Correct Answer: B

A pulsar is a rapidly rotating neutron star that emits beams of radio waves detectable from Earth as it spins.

Q68.A shooting star is ____?

Easy
A Sun
B A comet
C A meteor
D An asteroid
Planets PPSC

Correct Answer: C

A shooting star is actually a meteor — a small space rock burning up as it enters Earth's atmosphere.

Q69.Almost identical eclipses occur after 18 years and 11 days. This cycle is known as____?

Easy
A Partial Eclipse cycle
B Total Eclipse Cycle
C Saros Cycle
D None of the above
Planets PPSC

Correct Answer: C

The Saros Cycle is the period of about 18 years and 11 days after which the Sun, Earth, and Moon return to approximately the same relative positions, producing nearly identical eclipses.

Q70.Among the planets of the Solar system the position of the Earth from the Sun is:____?

Easy
A Second
B Third
C Fourth
D Sixth
Planets PPSC

Correct Answer: B

Earth is the third planet from the Sun in the Solar System.

Q71.Apart from Venus, which planet rotates from east to west?

Easy
A Jupiter
B Mars
C Uranus
D Neptune
Planets PPSC

Correct Answer: C

Besides Venus, Uranus also rotates from east to west (retrograde rotation), due to its extreme axial tilt.

Q72.As comets get close to the sun, they start to melt” and release gas and dust. This gas and dust forms what?

Easy
A “coma” around the comet’s nucleus and a long tail that points away from the sun
B “coma” that points away from the sun and a long tail around the comet’s nucleus
C Only “coma” around the comet’s nucleus
D Only a long tail that points away from the sun
Planets PPSC

Correct Answer: A

As comets approach the Sun, the heat causes ice to sublimate, releasing gas and dust that form a glowing 'coma' around the nucleus and a tail pointing away from the Sun.

Q73.At what angle above the horizon must the sun be to create a rainbow?

Easy
A 90 degrees
B 60 degrees
C 40 degrees
D 65 degrees
Planets PPSC

Correct Answer: C

A rainbow forms when the sun is at an angle of about 40 degrees or less above the horizon, opposite the observer.

Q74.At what time of day is the relative humidity normally at a minimum ____ ?

Easy
A When the air temperature is highest
B Just before sunrise
C About midnight
D When the air temperature is lowest
Planets PPSC

Correct Answer: A

Relative humidity is typically at its minimum in the afternoon when air temperature is at its highest, since warm air can hold more moisture.

Q75.Atmosphere is held in place by?

Easy
A Pressure of the planetary body
B Gravity of the planetary body
C Charge of the planetary body
D Heat of the planetary body
Planets PPSC

Correct Answer: B

A planet's atmosphere is held in place by its gravitational pull.

Q76.Atmospheric pressure is the force (per unit-area) perpendicular to a unit-area of planetary surface, as determined by ____.

Easy
A Mass of vertical column of atmospheric gases
B Mass of horizontal column of atmospheric gases
C Weight of vertical column of atmospheric gases
D Mass of vertical and weight of horizontal of atmospheric gases
Planets PPSC

Correct Answer: C

Atmospheric pressure is determined by the weight of the vertical column of air (atmospheric gases) above a given surface area.

Q77.Big Bang theory explains____?

Easy
A Origin of Universe
B Origin of Sun
C Laws of physics
D None of above
Planets PPSC

Correct Answer: A

The Big Bang theory explains the origin and expansion of the universe from an extremely hot, dense initial state.

Q78.Celestial body that affects tides of Ocean is?

Easy
A Sun
B Moon
C Galaxy
D Meteorites
Planets PPSC

Correct Answer: B

The Moon is the celestial body with the greatest influence on Earth's ocean tides, followed by the Sun.

Q79.Comets are made mostly of ice and dust. As comets get close to the sun, they start to melt and release what?

Easy
A Steam and dust
B Gas and dust
C Steam, gas and dust
D None of the above
Planets PPSC

Correct Answer: B

Comets are made mostly of ice and dust. As comets get close to the sun, they start to melt and release what: Gas and dust. Astronomical observations and measurements establish this relationship among the relevant celestial bodies.

Q80.Constellations referred to as zodiac, are____?

Easy
A Imaginary regions that encompass the path of the planets
B Signs of Roman gods
C A group of stars
D None of these
Planets PPSC

Correct Answer: A

Constellations referred to as zodiac, are Imaginary regions that encompass the path of the planets. This description follows from the defining characteristics and established facts associated with the subject.