一項有關非接觸力與磁力的問題

（一）磅 上面有塊磁石有多重。（二）凌空有塊磁石 由什麼力量支撑着。（三）凌空中有一件重物， 重物下有塊磁石， 這重物與兩塊磁石 正對正 使重物能凌空瓢起 問題之 凌空重物是己先存在，還是 兩塊磁石 正對正 使重物能凌空瓢起時オ存在…？

2011-07-11 21:41:38 補充：
知道答案了嗎…！在地球的上空，有三顆同歩人造通訊衞星，用以連結全球通訊網絡。其同歩之凌空原理由地球、月亮、太阳三者之間万有引力磁埸合力計算所得。您所提《假設有個Setup 是有一個磅》這Setup上的磅有多大，能力有多少…？那麼磅度到的重量是〔1塊磁石〕 定 〔2塊磁石+重物〕——在地球上的磅答案（一）磅 上面有塊磁石有多重。供参考！

The physics principle behind this problem is Newton's Third Law, action and reaction forces are equal in magnitude but opposite in direction.

First consider the weight with magnet underneath. Since the [weight and amgnet] is balanced by the magentic force in air, we have, at equilibrium, the following equation:

W + Wm = Fm
where W is the weight of the "weight"
Wm is th eweight of the magnet
Fm is the (upward) magnetic force

Now, consider the magnet that rests on the balance. We have,
R = Wm + Fm'
where R is the normal reaction acting on the magnet
Fm' is the (downward) magentic force acting on the magnet

By Newton's Third Law, the magnitudes of Fm and Fm' are equal.
hence, R = Wm + Fm
i.e. R = Wm + (W + Wm) = W + 2(Wm)

Therefore, the balance shows a reading on the weight of the "weight" plus that of the two magnets.

當然係後者，如果你體重有50KG，你雙手舉起50KG重石頭，你當時總重量有幾多呢﹖好簡單嘅加數啫﹗