题干

如图所示,杠杆AOB的A端挂重为GA的物体,B端挂重为GB的物体,杠杆平衡时AO处于水平位置,若AO=BO,杠杆自重不计,则GA和GB的大小关系是(   )

A:GA>GB

B:GA=GB

C:GA<GB

D:无法比较

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答案(点此获取答案解析)

C

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阅读下列短文,从下面每小题的A、B、C、D四个选项中选出最佳选项。

    Is your TV connected to the Internet? What about your chair, or your fridge? Probably they are not. But in the future, most things in your home may be connected, as the so-called "Internet of things" is developing.

    The Internet of things may be coming sooner than you think. In 2015, Samsung CEO spent a lot of time talking about the Internet of things. He said that in the next five years, every Samsung product will be part of the Internet of things, whether it's a vacuum cleaner or a washing machine.

    So, how do household objects that are part of the Internet of things work? Well, think of a common chair. When connected to the Internet, the chair warms up when it knows that the user has just walked into the room and is feeling cold.

    An Internet-connected camera could help people feel safer in their homes. It can recognize people's faces, and even can see when someone passes by and send you a message on your smartphone to let you know who's there. If the person is someone you don't know, it can tell you that, too.

    But according to MIT Technology Review, whether companies are connecting dog food bowls or security systems to the Internet, there may be some problems. For example, many early connected-home devices (装置) don't have much built-in security, which means they could be hacked (被黑客攻击). In addition, it could be difficult to get these devices to work together especially when they are made by different companies. To fight this, many companies have joined the Open Connectivity Foundation, which has more than 300 members now.

    So, picture this: you enter your home. The temperature changes to make you feel comfortable. Your favourite music starts playing for you. Do you think that this would be a good thing? It may happen sooner than you think.