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Question
Distinguish between:
Universal gravitational constant - Gravitational acceleration of earth.
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Solution
| Sr.no. | Universal gravitational constant | Gravitational acceleration of earth |
| 1. | The gravitational force acting between unit masses kept at a unit distance away from each other equals gravitational constant (G). | The acceleration produced in a body under the influence of the force of gravity alone is called gravitational acceleration of earth or acceleration due to gravity (g). |
| 2. | Gravitational constant is a scalar quantity. | Acceleration due to gravity is a vector quantity. |
| 3. | The value of a gravitational constant is a constant. | The value of acceleration due to gravity varies with height, depth and shape of the earth. |
| 4. | The value of G = 6.67 × 10-11 Nm2/kg2. | The value of g = 9.8 m/s2 on earth’s surface. |
| 5. | Gravitational constant is never zero anywhere. | Acceleration due to gravity is zero at the centre of the earth. |
| 6. | The S.I. unit of gravitational constant is Nm2/kg2 | The S.I. unit of acceleration due to gravity is m/s2. |
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