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: [[Weight]] always acts towards the centre of [[mass]] of a [[moon]], [[planet]] or [[star]].
: The [[weight]] of an [[object]] acts from its [[Centre of Mass|centre of mass]] (or [[Centre of Gravity|centre of gravity]]).
: On [[Earth]] the [[Gravitational Field Strength|gravitational field strength]] is roughly 9.8[[N/kg]]
===Example Calculations===
{| class="wikitable"
|-
| style="height:20px; width:200px; text-align:center;" |'''Calculate the [[weight]] of a 25[[kg]] object on [[Earth]] correct to two [[Significant Figure|significant figures]]'''
| style="height:20px; width:200px; text-align:center;" |'''A 550[[kg]] space probe is sent into deep space beyond the gravitational field of any other [[object]]. Calculate the weight of the space probe correct to two [[Significant Figures|significant figures]].'''
| style="height:20px; width:200px; text-align:center;" |'''[[The Moon]] has a [[Gravitational Field Strength|gravitational field strength]] of 1.6[[N/kg]]. Calculate the weight of a 85[[kg]] astronaut on [[The Moon]] correct to two [[Significant Figures|significant figures]].'''
|-
| style="height:20px; width:200px; text-align:left;" |
m = 25[[kg]]
g<sub>Earth</sub> = 9.8[[N/kg]]
<math>W = m \times g </math>
<math>W = 25 \times 9.8 </math>
<math>W = 245N </math>
<math>W \approx 250N </math>
| style="height:20px; width:200px; text-align:left;" |
m = 550[[kg]]
g<sub>Deep Space</sub> = 0[[N/kg]]
<math>W = m \times g </math>
<math>W = 550 \times 0 </math>
<math>W = 0.0N </math>
| style="height:20px; width:200px; text-align:left;" |
m = 85[[kg]]
g<sub>The Moon</sub> = 1.6[[N/kg]]
<math>W = m \times g </math>
<math>W = 85 \times 1.6 </math>
<math>W = 136N </math>
<math>W \approx 140N </math>
|}