Term
| What is Newton's Law of Universal Gravitation? |
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Definition
Newton's Law of Universal Gravitation describes how ALL objects attract each other's mass with a force of gravitational attraction.
The force of gravitational attraction is directly proportional to the masses of each of the objects and inversely proportional to the square of the distance that separates their centers. |
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Term
| What is the equation for gravitational force of attraction? |
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Definition
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Term
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Definition
The gravitational constant
G = 6.673 x 10-11 N m2 kg-2 |
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Term
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Definition
| distance between the centres of the masses is denoted by 'r' |
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Term
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Definition
| g is the gravitational field strength or the acceleration due to gravity - depends on the situation! |
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Term
| What are the units of 'g' |
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Definition
| When gfs the unit is N kg-1 but when acceleration due to gravity the unit is that of acceleration m s-2 |
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Term
| What is the gravitational field strength at a point? |
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Definition
| The gravitational force per unit mass at that point. |
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Term
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Definition
g = F/m
but F = GmM/r2
so, g = GM/r2 |
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Term
| Is Gravitational Field strength a scalar or vector quantity? |
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Definition
| Gravitational Field strength is a vector because it has a direction - is a force per unit mass (and force is a vector!). |
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Term
| Is gravitational potential a scalar or a vector? |
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Definition
| It is a scalar quantity - 'energy required' and energy is scalar! |
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Term
| What is meant by the gravitational potential at a point in a gravitational field? |
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Definition
| The gravitational potential at a point in a gravitational field is the work done against the field (or energy change) per unit mass [image] when an object is moved from infinity to the point [image] |
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Term
| State the relationship between the gravitational potential energy, Ep, and the gravitational potential, V, for a body of mass m placed in a gravitational field |
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Definition
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The relationship between them is that Ep equals the product of the mass m and the gravitational potential V
or Graviational potential is gravitational potential energy per unit mass (or per kg) |
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