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प्रश्न
Write the answer of the question with reference to laws of gravitation.
State the universal law of gravitation.
Answer the following question.
State Newton’s law of gravitation.
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उत्तर
The universal law of gravitation states that every object in the universe attracts every other object with a force called the gravitational force. The force acting between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centres.
F ∝ m M (masses of two bodies m and M)
F ∝ `1/"d"^2` (d is the distance between the two bodies.)
A and B are two bodies, the distance between which is given as d.
F = force with which one body is attracting the other.
G = proportionality constant.
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संबंधित प्रश्न
How does the force of gravitation between two objects change when the distance between them is reduced to half?
What is the magnitude of the gravitational force between the earth and a 1 kg object on its surface? (Mass of the earth is 6 × 1024 kg and radius of the earth is 6.4 × 106 m).
What happens to the force between two objects, if the mass of one object is doubled?
Answer the following:
An astronaut inside a small space ship orbiting around the earth cannot detect gravity. If the space station orbiting around the earth has a large size, can he hope to detect gravity?
Choose the correct alternative:
Acceleration due to gravity increases/decreases with increasing depth. (assume the earth to be a sphere of uniform density).
Choose the correct alternative:
Acceleration due to gravity is independent of mass of the earth/mass of the body.
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A rocket is fired from the earth towards the sun. At what distance from the earth’s centre is the gravitational force on the rocket zero? Mass of the sun = 2 ×1030 kg, mass of the earth = 6 × 1024 kg. Neglect the effect of other planets etc. (orbital radius = 1.5 × 1011 m).
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[Hint : If a line y = mx + c makes angle θ with the X-axis, m = tan θ.]
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People often shake the branches of a tree for getting down its fruits.
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Multiple Choice Question. Select the correct option.
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All objects in the universe attract each other along the line joining their________.
The force of attraction between any two material objects is called __________.
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Calculate the maximum height it would gain before it begins to fall.
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Where will you weigh more: at the moon's surface or at the earth's surface?
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Name and state the action and reaction in the following case:
A book lying on a table.
Name and state the action and reaction in the following case:
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Name and state the action and reaction in the following case:
Hammering a nail.
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State Newton's law of gravitation. What is the difference between:
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| Time (s) | Distance (m) |
| 0 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 27 |
Answer the following question.
State Newton’s law of gravitation and express it in vector form.
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State the universal law of gravitation and derive its mathematical expression.
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The gravitational force between a hollow spherical shell (of radius R and uniform density) and a point mass is F. Show the nature of F vs r graph where r is the distance of the point from the centre of the hollow spherical shell of uniform density.
The gravitational force between a hollow spherical shell (of radius R and uniform density) and a point mass is F. Show the nature of F vs r graph where r is the distance of the point from the centre of the hollow spherical shell of uniform density.
Find the gravitational force of attraction between the ring and sphere as shown in the diagram, where the plane of the ring is perpendicular to the line joining the centres. If `sqrt8` R is the distance between the centres of a ring (of mass 'm')and a sphere (mass 'M') where both have equal radius 'R'.
Newton's universal law of gravitation applies to ______.
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