# Yahoo奇摩 網頁搜尋

1. ### 什麼是DC motor and AC motor ?

...電動機又分為交流電動機及直流電動機以用於不同的場合。 直流電動機DC motor 的好處為在控速方面比較簡單，但此類電動機不宜在高溫、易燃等環境下操作...

2. ### dc motor 的疑問!

... same as 2(b) 5. This is the purpose of using a motor , for example the motor in an eelctric fan. 6. Permanent magents ...

3. ### Ac motor

Use the equation, rpm = 2f x 60/p where rpm is rotational speed of the motor f is the frequency of the ac supply p is the number of magnetic...

4. ### dc motor

..., 115 = 2 x (30x10^-3) x 400N/(60x2) where N is the motor speed in rpm N = 575 rpm

5. ### How does an electric motor work?

An electric motor uses the attractive and repulsiveforces between magnetic... are electromagnets. In a typical motor , theseelectromagnets are designed so that...

6. ### 天同師兄,有關dc. motor ,請回答

Q: 個 motor 冇current都可以郁,power=i V,咁iput power除左starting motor 果陣之外..., you are right. This is really the case for an ideal motor under a "no load" condition. At starting, the motor acquires...

7. ### f.3 physics ( motor )

...current in the coil every time the coil pass through the vertex. This can ensure the motor to rotate in one direction. ci. cii. di. the motor may not rotate properly as the...

8. ### power of motor

...out, the work done by the back emf equals to mechanical output of the motor . i.e. (current)(back emf)=(torque)(angular velocity) hence, back emf/angular velocity = torque/current...

9. ### Why there is force for motors

...'s right hand rule to determine the direction of the current flow. For motors , as there is a current flow and magnetic field, so a force will exert on the motor ...

10. ### What physic principles are used for the electric motor ?

An electric motor uses the attractive and repulsiveforces betweenmagnetic poles to... least some ofthe magnetsare electromagnets. In a typical motor , theseelectromagnets aredesigned so that their poles change...