Physics
Gravitation and Center of Mass
368 Questions
Gravitation and center of mass questions explore gravitational fields, planetary density, and the mechanics of celestial bodies. Test items include calculating gravitational strength on different planets and understanding the Roche Limit. This topic is essential for the physics syllabus of major competitive exams.
Gravitational fieldCenter of massPlanetary densityHill SphereSpace-time curvature
Gravitation and Center of Mass Questions
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Mass is equal on both planets
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Mass is higher on Earth if there’s less gravity
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Mass is lower on Sakaar if there’s more gravity
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Mass is 100 times greater on Earth
A
Correct answer
Explanation
Mass is an intrinsic property of an object and remains constant regardless of the gravitational field or location. Weight changes based on gravity, but mass does not.
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four times as great.
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twice as great
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the same
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half as great
B
Correct answer
Explanation
Newton's Law of Universal Gravitation states that the gravitational force between two objects is directly proportional to the product of their masses. If the Earth's mass were doubled while the Sun's mass and the distance between them remained constant, the gravitational force would become twice as great.
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it is closer to the Sun
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it has more mass than Earth
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it has less mass than Earth
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it has a thicker atmosphere
C
Correct answer
Explanation
Gravitational force is directly proportional to the masses of the interacting objects. Since Mars has significantly less mass than Earth, its gravitational pull on objects is weaker.
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the gravity on Mars is more than Earth's
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the gravity on Mars is less than Earth's
B
Correct answer
Explanation
Weight is the measure of the gravitational force acting on an object's mass. Since the woman weighs less on Mars than on Earth, Mars must have a weaker gravitational pull.
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because their masses are so great
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because Earth's rotational speed is so fast
A
Correct answer
Explanation
Although gravity decreases with distance, the gravitational force also depends on the masses of the objects. The immense masses of both the Sun and the Earth allow for a strong gravitational attraction despite the vast distance between them.
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mass & speed
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speed & distance
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distance & mass
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magnetism & distance
C
Correct answer
Explanation
According to Newton's law of universal gravitation, the gravitational force between two objects is determined solely by their masses and the distance between them. Speed and magnetism do not affect gravitational force.
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9.2 m/s2
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9.8 m/s2
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8.9 m/s2
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10.3 m/s2
B
Correct answer
Explanation
The acceleration due to gravity near the Earth's surface is approximately 9.8 m/s^2. This value represents how fast an object accelerates when in free fall under the influence of Earth's gravity.
A
Correct answer
Explanation
According to Newton's third law of motion, forces always occur in equal and opposite pairs. Therefore, the gravitational force you exert on the Earth is equal in magnitude to the gravitational force the Earth exerts on you.
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It weighs more because the gravity on the moon is more
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It weighs more because in space there is no gravity
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It weighs more because the gravity of Earth is greater
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It weighs the same weight does not change
C
Correct answer
Explanation
Earth's gravitational acceleration (9.8 m/s²) is about 6 times stronger than the Moon's (1.6 m/s²). While mass remains constant, weight depends on gravity, so the object would weigh more on Earth.
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mass and distance
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size and density
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weight and volume
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composition and location in the Universe
A
Correct answer
Explanation
According to Newton's law of universal gravitation, the force of gravity between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
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the amount of matter in an object
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The amount of space an object takes up
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The amount an object weighs on the moon
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The physical form of an object (solid, liquid, or gas)
A
Correct answer
Explanation
Mass is defined as the total amount of matter or substance contained within an object, which remains constant regardless of location.
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Equal to the force of the Earth on the Moon
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Is the negative of the force of the Earth on the Moon
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is one sixth the force of the Earth on the Moon
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Is negative one sixth the force of the Earth on the Moon
B
Correct answer
Explanation
According to Newton's Third Law, forces exist in action-reaction pairs that are equal in magnitude and opposite in direction. Therefore, the force of Earth on the Moon is the negative of the force of the Moon on Earth.
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The mass and radius of the Sun
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the mass and radius of Mars
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the mass of the Sun and the radius of Mars
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The Sun's mass and the average distance from Mars to the Sun
B
Correct answer
Explanation
In the formula a_grav = GM/r^2, M represents the mass of the central body creating the gravitational field, and r represents the distance from the center of that body. For Mars, these are the mass and radius of Mars.
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The mass of the star it orbits
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The mass of the planet itself
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The gravitational constant, G
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The distance from the star it orbits
B
Correct answer
Explanation
Gravitational acceleration on a planet's surface is determined by the planet's mass and radius (g = GM/r^2). The mass of the star it orbits does not affect the surface gravity of the planet itself.
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The gravitational constant
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given in Nm2/kg2
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6.7x10-11
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All of the above
D
Correct answer
Explanation
In F = G(m1m2/r^2), G is indeed the gravitational constant, its units are Nm^2/kg^2, and its approximate value is 6.67 x 10^-11 Nm^2/kg^2.