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  • 电动汽车

    Comparison of an all-electric vehicle and a hybrid vehicle parked side by side.

    As gas prices continue to rise, electric cars and hybrids are becoming increasingly popular. These cars are certainly a part of our future. On the left in the image above is an all-electric vehicle, and on the right is a hybrid vehicle that uses gas part time and electricity part time.
    ::随着天然气价格的不断上涨,电动汽车和混合汽车越来越受欢迎。 这些汽车当然是我们未来的一部分。 以上图像的左边是全电车,右边是使用半时和半时天然气的混合汽车。

    Electric Motors
    ::电动汽车

    In an earlier concept, we described and calculated the force that a exerts on a current carrying wire. Since you are familiar with Newton’s third law of motion , you know that if the magnetic field exerts a force on the current carrying wire, then the current carrying wire also exerts a force of equal magnitude and opposite direction on the magnetic field.
    ::在早先的一个概念中,我们描述并计算了对电流承载电线施加的威力。 既然你熟悉牛顿的第三种运动法则,你知道,如果磁场对电流承载电线施加了威力,那么电流承载电线对磁场也产生同等强度和相反方向的威力。

    Circuit connecting a battery with a coil in a magnetic field indicating forces on wires.

    In the sketch above, a is connected to a battery, with one part of the circuit placed inside a magnetic field. When current runs through the circuit, a force will be exerted on the wire by the magnetic field, causing the wire to move. If we choose to consider electron current in this case, the electrons flow from the back of the sketch to the front while the magnetic field is directed upward. Using the left hand rule for this, we find that the force on the wire is to the right of the page. Had we chosen to consider the current to be conventional current , then the current would be flowing from the front of the sketch to the back and we would use the right hand rule . The force on the wire would, once again, be toward the right.
    ::在上文的草图中,一个电路与电池相连,其中一部分电路被放置在磁场内。当电流穿过电路时,磁场将对电线施压,导致电线移动。如果我们选择考虑在这一情况下电子电流,电子从草图的背面流向前面,而磁场则向上。使用左手规则,我们发现电线上的电力在页面右侧。如果我们选择将电流视为常规电流,那么电流就会从草图前面流向背部,我们就会使用右手规则。电线上的电力将再次流向右侧。

    Electrical motors change electrical energy into mechanical energy . The motor consists of an electrical circuit with part of the wires inside a magnetic field. This can be seen below. Positive charges move through the circuit in the direction of the light purple arrows. When the charges move up through the part of the coil that is right next to the north pole, the right hand rule tells us that the wire suffers the force, F , pushing the wire in the direction of the blue arrow, toward the back of the sketch. On the other side of the coil, where the charges are moving down through the field, the right hand rule shows the force would push this side of the coil toward the front. These two forces are working together, rotating the coil in the direction of the circular red arrow. 
    ::电动马达将电动能量转换为机械能。 电动马达由电路组成, 有一部分电线在磁场内。 如下所示: 正面电荷在电路中向光紫箭的方向移动。 当电荷在电线圈的右侧移动时, 右手规则告诉我们电线受到电力的影响, F, 将电线线推向蓝箭的方向, 向草图的背面。 在电线圈的另一侧, 电荷通过田向下移动, 右手规则显示电力会将电线圈的这一侧推向前方。 这两个部队一起工作, 向圆红箭的方向旋转电线圈。

    An Electric Motor With A Rotating Coil In A Magnetic Field.

    Where the rotating coil (in grey) meets the wires attached to the power source (black), we find a split ring commutator . The coil turns, but the commutator and power source do not. As the coil turns, it moves off of the blue box connector and as it continues to turn, it connects to the other blue box connector. As the coil turns, it reverses its connections to the external circuit. Therefore, inside the coil, the current is always flowing in the same direction because the left side of the coil is always attached to the left side of the external circuit. This allows the coil, or armature , to continue to spin the same direction all the time.
    ::当旋转线圈(灰色)与电源(黑色)连接的电线相匹配时,我们就会发现一个分裂环形通路器。圆圈旋转,但通电器和电源没有。在旋转线圈转动时,它从蓝箱连接器中移动,随着它继续转动,它会连接到另一个蓝箱连接器。在旋转线圈转动时,它会逆转与外部电路的连接。因此,在圆圈内,电流总是向同一方向流,因为圆圈的左侧总是与外部电路的左侧相连。这使得圆圈或机械能继续旋转同一方向。

    In electrical motors, these coils often consist of not just one, but many wires, as can be seen here:
    ::在电动机中,这些线圈往往不仅包括一条电线,而且包括许多电线,如下文所示:

    A cross-section of an electric motor showing wire connections and coils.

    Launch the Electric Motor simulation below to visualize how we convert electrical energy into mechanical energy to create a motor. When experimenting with the simulation, you can manipulate the size of the motor, the strength of the input current, the strength of the magnetic field, and the number of turns in the wire:
    ::启动下面的电动汽车模拟, 以便直观地显示我们如何将电能转换成机械能源来制造电机。 当进行模拟实验时, 您可以操纵电机的大小、 输入电流的强度、 磁场的强度, 以及电线中的旋转次数 :

    Summary
    ::摘要

    • When current runs through the circuit, a force will be exerted on the wire.
      ::当电流穿过电路时,电线将受到力压。
    • An electrical motor changes electrical energy into mechanical energy.
      ::电动发动机将电能转化为机械能源。
    • A split ring commutator keeps the current in the coil flowing in the same direction even though the coil changes sides every half turn.
      ::一条分形环环通器使电流在循环中向同一方向流动,即使每半个转折圈的侧面会改变。

    Review
    ::回顾

    1. Which way will the wire be pushed when current passes through the wire?
    ::1. 当电流穿过电线时,电线会以何种方式推推?

    1. up
      ::上上
    2. down
      ::向下下下
    3. left 
      ::左左
    4. right
      ::右右右右右
    5. None of these.
      ::没有一个这些。

    Diagram of an electric motor showing magnetic fields and battery connections.

     

    2. Which way will the coil spin when current passes through the wire?
    ::2. 当洋流穿过铁丝网时,圆圈会以什么方式旋转?

    1. clockwise
      ::时顺时针
    2. counterclockwise
      ::逆时针反时针

    Setup showing a battery connected to a coil in a magnetic field.

     

    Explore More
    ::探索更多

    Use this resource to answer the questions that follow.
    ::使用此资源回答下面的问题 。

     

    1. Who first built an electric motor?
      ::谁先造的电动马达?
    2. What size battery was used in the video motor?
      ::录像机中使用的电池大小是多少?