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19 Jan 2010 15:47:18 IST

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what is g'?

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what is g'?

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Aditya

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19 Jan 2010 16:48:51 IST

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acceler ation due to gravity..in general...u r asking as in what ..be specific

edison

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19 Jan 2010 16:52:40 IST

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Consider an object of mass m lying on or near the surface of the Earth. Let M_e be the mass of the Earth and R_e be its radius i.e., R_e is the distance between the object and the centre of the Earth.

According to Newton's law of gravitation, the force of attraction (F) between the Earth and the object is

A Body of Mass m Lying on the Surface of the Earth

According to Newton's second law of motion this force produces an acceleration (g) in the object.

F = ma (a = g)

F = mg

Substituting the value of F in equation (2) we get,

From equation (3) it is very clear that acceleration due to gravity does not depend on the mass m of the object. It only depends on the mass of the Earth (M_e) and the distance from the centre of the Earth to the object.

Numerical Value of Acceleration due to Gravity on Earth

Gravitational Constant (G) = 6.6734 x 10^-¹¹ Nm²/kg²

Mass of the Earth (M_e) = 6 x 10²⁴ kg

Radius of the Earth (R_e) = 6.4 x 10⁶ m

The value of acceleration due to gravity on Earth is 9.8 m/s². This means that when a body falls freely towards the Earth its velocity increases at the rate of 9.8 m/s during its motion. Similarly when an object is projected vertically upwards its velocity decreases at the rate of 9.8 m/s and eventually the velocity becomes zero. The height at which the velocity of an object moving against gravity becomes zero is described as the maximum height attained by the object. When the velocity becomes zero the object starts falling down, with an acceleration as if released from that height.

Note :

The acceleration produced in a body moving against gravity is also 9.8 m/s² but oppositely directed therefore g = - 9.8 m/s².

Deevita Agarwal

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7 Apr 2010 21:19:14 IST

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g is acceleration due to gravity.

» ÆoniuM XEonAX «

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7 Apr 2010 21:43:26 IST

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g is 7th letter in english alphabets

palash chauhan

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8 Apr 2010 16:11:08 IST

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acceleration due to gravity is basically "g" and its val is 9.8 m/s raised to power -2

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