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CBSE Class 9 Answered

If the radius of  Earth was to be increased by a factor of 3. By what factor would its density have to be changed to keep the value of  'g' the same.
Asked by acv27joy | 20 Apr, 2018, 07:50: PM
answered-by-expert Expert Answer
acceleration due to gravity g is given by
 
G, M, R, ρ and V are Gravitational constant, mass of earth, radius of earth, density of earth and volume of earth respectively.
 
Hence if radius R increases by factor of 3, then density ρ should decrease by a factor of 1/3
Answered by Thiyagarajan K | 21 Apr, 2018, 01:03: PM

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CBSE 9 - Physics
An object of mass 1kg is falling from the height h=10m.calculate a) the total energy of an object at h=10m b) potential energy of the object when it is at h=4m c) kinetic energy of the object when it is at h=4m d) what will be the speed of the object when it hits the ground
Asked by mailtoparvathyprajith | 08 Feb, 2024, 06:45: PM
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:50: PM
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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