# Yahoo奇摩 網頁搜尋

1. ### EPE of a neutral object?

...neutral object should have zero potential, unless the object is under the action of an external electric field. The electric potential of an atom is zero, because the ...

分類：科學及數學 > 物理學 2016年12月04日

... a system, -ve work needs to be done by an external agent ( external force ). In other words, energy is absorbed by that external agent...

分類：科學及數學 > 物理學 2016年09月11日

3. ### escape velocity

... on it. But in the situation you described, there is an external force , gravity, that acts on the object during its motion.

4. ### phy question

1. Electric field at mid-point = [k(-8x10^-6)/0.04 + k(7x10^-6)/0.04] v/m where k is the Coulomb constant (=9x10^9 N.m^2/C^2) The direction of the field is towards the -ve charge. 2. These are standard electric field diagrams, which you could find in...

5. ### phy E&M

...bottom. Since a magnet tends to align with the external magnetic field lines, the coil will move with its...with the field lines. 2.Yes, direction of magnetic force is pointing horizontally towards the right. ...

6. ### 碰撞問題(物理科的能量不滅27/07/14)

...will decrease... 2014-07-30 16:17:42 補充： (cont'd)... The pushing force on B will cease when the speed of B is equal to or greater...

7. ### F.4 2條 Phy題 溫書唔識幫幫手 10分

...only valid on an isolated system. That is, there is no external force acting on the syste. Here in the example, the wall provides an...

8. ### dc motor's energy conservation

..., to keep the coil continuously rotating at constant speed, an external force ( external torque) must be applied to the coil. It is the mechanical...

9. ### [20]摸胸女朋友話成長期會痛 點算?

... at about 18 years old the pain could be by her own or external force 1. when her breasts grow, her skin will stretch which cause...

10. ### 小巴西龜出現斷頸既問題

They must be fighting, normally the neck won't break, unless they fall, or fight, or unknown personal use external force to break their neck.

分類：寵物 > 魚兒 2013年11月20日