人在齐胸深的水中时，会感到轻飘飘的，这是因为（） A．人_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题选择题

人在齐胸深的水中时，会感到轻飘飘的，这是因为（　　）

A．人在水中受到的重力变为零

B．人在水中受到的重力变小了，但不为零

C．人在水中受到水对他向上的浮力

D．人在水中受到水对他向下的压力

答案

人之所以会感觉轻飘飘的，是因为受到了水给人的浮力，而人的重力是不会发生变化，至于压力，由于身体各部位所受压力的抵消，水给人的压力比较微弱．

故选C

情景交际

情景对话.

M:Hi,Lily,how's your new flat?

W:It's great.I really like it.

M:__1__

W:It's one big room,but it has a bathroom and a small kitchen,too.

M:__2__

W:It's only about 10 minutes.

M:10 minutes by bus or by car?

W:__3__I walked to work this morning.I was 10 minutes early.

M:You are lucky.I was 10 minutes late.

W:__4__

M:All the buses came late.

W:What did your boss say?

M:She was late too.

W:What happened to her?

M:__5__

W:Well,then you're really lucky after all.But what are you going to do tomorrow?

M:I'll start 15 minutes earlier.

A．Is it big?

B．What happened?

C．How far is it from the office?

D．She took the train,and it was late too.

E．On foot.

F．How big is it?

G．What time is it?

判断题

硅钢片DQ230-35比DQ200-50的铁损小。