7th Class General Science Unit 12 Earth and Space MCQs (زمین اور خلا) | PAKMCQs

Force of gravity is correct because the mutual attractive force between any two masses in the universe is defined as the force of gravity.

Massive objects like planets is correct because gravitational attraction is proportional to mass, making it prominent for massive astronomical bodies.

Sun has huge mass is correct because the Sun contains 99.8% of the solar system's mass, generating an extremely strong gravitational field.

Sir Isaac Newton is correct because Sir Isaac Newton formulated the Universal Law of Gravitation in 1687.

Because of its massiveness is correct because an object's gravitational pull is directly determined by its total mass and massiveness.

Sun's gravitational pull is correct because all planets are bound in their orbits by the Sun's continuous gravitational pull.

Move the planets around itself in their orbits is correct because solar gravity acts as the centripetal force holding planets in stable orbital motion.

Immediately travel straight in the direction of speed is correct because due to inertia, objects without a centripetal force fly off tangentially in a straight line.

Gravity is correct because the gravitational pull between the Sun and planets provides the essential centripetal force for orbital revolution.

Inertia is correct because inertia is the resistance of any physical object to any change in its velocity or state of rest.

Because of its mass is correct because greater mass directly gives an object greater inertia, resisting motion changes.

Due to inertia is correct because rotational inertia causes the blades to maintain their rotational state of motion until friction slows them.

Due to air resistance is correct because opposing forces like air drag and bearing friction gradually remove rotational energy.

They have a lot of inertia is correct because their immense mass gives them huge forward inertia, perfectly balanced by the Sun's gravity in vacuum.

Centripetal force is correct because the center-seeking force that continuously curves an object's path into a circle is centripetal force.

Centripetal force is correct because the tension in the string provides the necessary centripetal force to maintain circular motion.

Moves it in circle is correct because centripetal force continually redirects the velocity vector, forcing the object into a circular path.

Ball goes straight toward A not toward B is correct because releasing the string removes centripetal force, allowing inertia to carry the ball tangentially straight ahead (toward A).

Natural satellite of our earth is correct because the Moon is a celestial body naturally orbiting our planet Earth as its natural satellite.

Force of gravity is correct because Earth's mass exerts an inward force of gravity holding the Moon in its orbit.

Revolves around the earth is correct because gravitational acceleration continually curves the Moon's trajectory so it revolves stably around Earth.

At point "A" is correct because low initial velocity causes gravity to pull the projectile down nearby at point A.

At point "B" is correct because higher horizontal velocity allows the ball to travel further before gravity brings it down at point B.

It will start orbiting the earth without falling on earth is correct because reaching orbital velocity matches the Earth's curvature, so it falls perpetually around Earth without hitting it.

Satellite is correct because an object that enters continuous orbital path around a planet is defined as a satellite.

Sun is correct because our planet Earth completes an annual orbital revolution around the Sun.

Particles i.e., atoms and molecules is correct because all physical matter in the universe is structurally composed of atoms and molecules.

Mass is correct because the fundamental scalar measure of the total quantity of matter contained within an object is mass.

Kilogram (kg) is correct because the base standard unit for measuring mass in the International System of Units (SI) is the kilogram (kg).

Smaller: gram (g) & milligram (mg), Bigger: ton is correct because grams and milligrams measure smaller masses while metric tons measure large bulk masses.

1000 kg is correct because 1 metric ton equals exactly 1000 kilograms (1 ton = 1000 kg).

1000 g is correct because metric kilo prefix represents 10³, meaning 1 kg = 1000 grams.

1000 mg is correct because 1 gram contains exactly 1000 milligrams (1 g = 1000 mg).

kg is correct because daily groceries and vegetables are commercially quantified in kilograms (kg).

grams is correct because precious metals like gold and silver jewelry are precisely weighed in grams (g).

milligram is correct because pharmaceutical tablet dosages contain tiny active ingredient quantities measured in milligrams (mg).

Physical balance is correct because mass is traditionally and accurately measured by comparison using a physical balance or beam balance.

All of the above is correct because electronic balances, beam balances, weighing scales, and truck weighbridges are all devices used to measure mass.

10 kg is correct because mass is an intrinsic property that remains constant at 10 kg regardless of location.

Because changing location causes no change in amount of matter is correct because the number of atoms and quantity of matter inside the body remains identical.

Weight of the body is correct because the gravitational force pulling an object towards Earth's center is defined as weight (W = mg).

Newton (N) is correct because weight is a gravitational force, so its SI unit is the newton (N).

Spring balance or force meter is correct because extension in a calibrated spring measures the downward force using a spring balance (newton meter).

W = m × g is correct because weight equals mass multiplied by local gravitational field strength: W = mg.

9.8 newton per kilogram (or 10 N/kg) is correct because standard surface gravity on Earth accelerates mass at 9.8 N/kg (approx. 10 N/kg).

20 N is correct because W = m × g = 2 kg × 10 N/kg = 20 N.

100 N is correct because W = 10 kg × 10 N/kg = 100 N.

6 times less is correct because the Moon's surface gravity is roughly one-sixth (6 times less) of Earth's gravity.

6 times less than that of earth is correct because g_moon is approximately 1/6th the gravitational strength of Earth.

g_moon = 1/6 (g_earth) is correct because the Moon's gravitational strength is mathematically expressed as g_moon = 1/6 (g_earth).

1.6 N/kg is correct because taking 1/6 of 9.8 or 10 N/kg gives approximately 1.6 N/kg (or 1.62 m/s²).

Force of only 1.6 N is correct because W = m × g = 1 kg × 1.6 N/kg = only 1.6 N of gravitational attraction.

16 N is correct because W = 10 kg × 1.6 N/kg = 16 N on the Moon's surface.

Earth: 100 N, Moon: only 16 N is correct because Earth pulls with 100 N (10×10) while the Moon pulls with 16 N (10×1.6).

6 times more height is correct because jump height is inversely proportional to gravity, allowing a jump 6 times higher on the Moon.

Because gravity on moon is not zero is correct because the Moon has mass and a non-zero gravitational pull (g ≈ 1.6 N/kg).

In space, far from massive objects is correct because true zero-gravity conditions occur in deep space far away from massive celestial objects.

Tides is correct because the cyclical rise and fall of coastal ocean water levels is defined as tides (ocean tides).

High tides is correct because when water reaches its highest crest elevation, it is a high tide.

Low tide is correct because the minimum retreating water stage is called a low tide.

Gravitational pull of moon and earth, spinning of earth is correct because tides are driven by lunar/solar gravitational gradients and Earth's daily rotation.

Oceans, land, structures, and people is correct because gravity affects all matter universally, pulling oceans, landmasses, buildings, and living beings.

Ocean water is correct because fluid liquid water bulges easily in response to tidal forces, making the impact on ocean water most evident.

High tide on Earth's side closest to the Moon is correct because differential gravity pulls the oceans into a prominent high tide bulge facing the Moon.

Flow of water against weak gravitational pull because of inertia is correct because rotational centrifugal effect and inertia create a second high tide bulge on the opposite side.

High tides is correct because surging water during a high tide can rapidly submerge beaches and cut off pathways.

Lifeboats is correct because coastal rescue teams deploy lifeboats to extract people trapped by incoming tides.

Spins around its tilted axis and revolves around Sun is correct because Earth performs daily axial rotation and an annual orbital revolution.

Involves day and night is correct because the 24-hour diurnal rotation alternately exposes sides to sunlight, causing day and night.

Involves change in seasons is correct because orbital revolution combined with axial tilt produces the annual cycle of changing seasons.

North Pole and South Pole is correct because Earth's geographical rotational axis terminates at the North Pole and South Pole.

Equator is correct because the great circle around Earth equidistant from the poles at 0° latitude is the Equator.

23.5° is correct because Earth's axial tilt (obliquity) is fixed at approximately 23.5 degrees.

Axis is correct because the imaginary line passing from the North to South pole around which Earth rotates is the axis.

Axial tilt is correct because the angle between the rotational axis and orbital normal is defined as axial tilt (obliquity).

Earth's tilted axis is correct because the 23.5° tilt causes hemispheres to receive varying angles of sunlight as Earth orbits the Sun.

Nearest in summer and farthest in winter is correct because a common misconception assumes summer is caused by physical proximity to the Sun.

Affects temperature but not significant is correct because minor orbital ellipticity has negligible temperature impact compared to axial tilt.

Due to orientation/facing direction is correct because changing orientation alters the angle of incident radiation, demonstrating how Earth's axial tilt alters solar intensity.

Summer season is correct because tilting towards the Sun brings direct, concentrated rays and longer days, producing summer.

Winter season is correct because tilting away from the Sun receives slanted rays and shorter days, resulting in winter.

Spring and autumn is correct because the transitional equinox periods between summer and winter are spring and autumn (fall).

Constellation is correct because an imaginary pattern or recognizable shape formed by a cluster of stars is a constellation.

All of the above is correct because Orion, Leo, and Taurus are all internationally recognized stellar constellations.

Locate or position themselves is correct because navigators historically used fixed constellations to orient directions and determine geographic positions.

Motion of Earth around our Sun is correct because Earth's annual orbital motion continuously alters our nighttime view of the celestial sphere.

Different direction in space is correct because Earth is on the opposite side of its orbit, facing our night sky in a completely different direction in space.

Due to axial tilt of the earth is correct because axial tilt combined with revolution continuously changes the visible elevation and position of star groups.

Northern hemispheres and southern hemispheres is correct because the Equator divides Earth into the Northern and Southern Hemispheres.

Due to tilt of the earth is correct because the 23.5° axial tilt shifts which hemisphere is directly angled toward the Sun during its orbit.

Summer in Northern, winter in Southern is correct because the tilted North hemisphere enjoys summer while the angled-away South hemisphere experiences winter.

Summer in Southern, winter in Northern is correct because direct sunlight falls on the South, bringing summer to Southern and winter to Northern Hemisphere.

Summer in Australia is correct because opposite hemispheres experience opposite seasons, so Pakistan's winter is Australia's summer.

Fall or autumn is correct because following summer, temperatures decline during the transitional season of fall or autumn.

Summer Solstice (Summer in North Hemisphere, No Sunlight on South Pole) is correct because 21 June marks the Northern Summer Solstice.

Autumnal Equinox (Fall Northern Hemisphere) is correct because 23 September is the Autumnal Equinox when day and night are equal.

No Sunlight on North pole and Summer in South Hemisphere is correct because 22 December is the Winter Solstice in the North and Summer Solstice in the South.

Vernal Equinox (Spring Northern Hemisphere) is correct because 21 March marks the Vernal (Spring) Equinox in the Northern Hemisphere.

Tilted relative to the orbital plane is correct because Earth's axis maintains a permanent 23.5° tilt relative to the perpendicular orbital plane.

Gravity is correct because the mutual gravitational attraction between the Sun and planets keeps planets locked in their orbits.

Mass is correct because the measurement of the amount of matter contained in a body is its mass.

Weight of the body on earth is correct because weight is the force exerted by Earth's gravity pulling an object towards its core.

Gravitational field strength (g) is correct because gravitational force per unit mass (F/m) defines gravitational field strength (g).

Tides is correct because the regular periodic rise and fall of coastal water levels are known as tides.

Constellation is correct because a recognizable geometric stellar pattern observed in the night sky is a constellation.

Tilted at some angle is correct because Earth's axis is inclined at an angle of 23.5° from the orbital perpendicular.

Northern and southern hemispheres is correct because the planet is bisected by the Equator into the northern and southern hemispheres.

Winter in Southern Hemisphere is correct because opposite hemispheres experience inverted seasonal cycles due to axial tilt.

Newton is correct because weight is a force, making its official SI unit the newton (N).

20 kg is correct because mass measures the invariant quantity of matter and remains exactly 20 kg on the Moon.

50 N is correct because W = m × g = 2 kg × 25 N/kg = 50 N.

Autumn is correct because when one hemisphere experiences spring equinox conditions, the opposite hemisphere experiences autumn (fall).

All of these is correct because lunar gravity, solar gravity, and planetary rotation collectively drive ocean tides.