放在水平桌面上的大烧杯内盛满了水，轻轻放入一小球后，从烧杯中_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题选择题

放在水平桌面上的大烧杯内盛满了水，轻轻放入一小球后，从烧杯中溢出100g的水，则下面判定正确的是：

A．小球受到的浮力为1N

B．小球质量不会等于100g。

C．小球的体积一定大于100cm³.。

D．水对烧杯底的压强会增大

答案

答案：A

A、根据阿基米德原理，物体受到的浮力等于排开液体受到的重力，由于烧杯中的水是满的，所以物体受到的浮力F_浮=G_排=mg=0.1kg×10N/kg=1N,所以A正确。

B、根据阿基米德定律，知道小球质量等于100g。

C、由于小球处于什么状态不清楚，所以小球的体积和排开液体的体积不确定，所以无法判定。

D、根据公式，水的密度不变，深度不变，所以水对烧杯底的压强不变。

完形填空

阅读下面短文，从短文后各题所给的四个选项、(A、B、C和D)中，选出可以填人空白处的最佳选项。
I became a gardener when I was twelve. My early__1___of gardening may not have originated from my love for nature. It was to ___2____my parents.
At that time, we had a big yard in which a beautiful maple tree stood. But my mother often looked with __3___at this work of natural art. Those golden leaves seemed like tons of rubbish her, “something else to ___4___!”Seeing the neighbors busy with gardening, my father ever thought it a waste of time.
At that age, I always did something___5_____to whatever my parents did! If gardening were something they found____6___,I would plant a garden!
I planted some lily（百合花）seeds in the yard. But they failed to ___7___.I continued to sunflower seeds and roses, Wild ____8_____joy,I found the first rose bloom（开花）.One by one, the flowers bloomed their heads off.__9___,I was touched by this land of wonder.
___10___,my parents showed no interest in my garden. My father even___11_____at me because found it was ___12___to move around my garden to the driveway. To my mother’s ___13__,I put her vase my real roses which, in her eyes, were simply weeds____14___flowers.
Regardless of their ____15___,I kept on planting my garden and ___16___to enjoy the pleasure gardening. Plants make such good companions: they breathe, they bloom, they____17____to care and love.
It has been many years since I made my first garden out of my desire to ____18___my parent .Today I become known as Mrs. Greenthumbs, teaching gardening and hosting a gardening show which makes my parents feel very____19_.And now I could say it is my affection for____20___that makes me a real gardener.

B．appreciation

D．interesting

D．get through

B．troublesome

B．displeasure

C．rather than

B．encouragement

B．comfortable

D．disappointed

单项选择题

ARP协议属于(1)层，其作用是(2)。

2（）

A．由MAC地址求IP地址

B．由IP地址求MAC地址

C．由IP地址查域名

D．由域名查IP地址