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Gravitational Fields. Gravitational Field Strength. Defined as the force per unit mass acting on a mass placed at that point. Gravitational field strength is a vector quantity. The units of gravitational field strength are Nkg -1. Gravitational Field.
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Gravitational Field Strength Defined as the force per unit mass acting on a mass placed at that point. Gravitational field strength is a vector quantity. The units of gravitational field strength are Nkg-1
Gravitational Field A region in 3D space where a force is experienced by a mass in that field. The force is always an attractive force, unlike magnetic and electrostatic forces.
Field Lines Field lines are used to represent gravitational fields. Parallel lines represent a uniform field strength.
Newton’s Law of Gravitation Newton’s law states that two point masses attract each other with a force that is proportional to the product of their masses and inversely proportional to the square of their separation. This is given by; F=Gm1m2/r2
Gravitational Field Strength of a Point Mass The gravitational field strength of an isolated point mass is given by; g = Gm / r2
Value of g on Earth On the surface of the Earth the gravitational field strength is approximately constant and equal to the acceleration of free fall. This is given as 9.81 ms-2