高中物理必修2同步习题:5.7 生活中的圆周运动

适用年级:高一
试卷号:161942

试卷类型:课时练习
试卷考试时间:2018/2/24

1.选择题(共2题)

1.阅读理解

    Do you love Beats headphones, True Religion jeans, and UGG shoes? These are some of the most popular brands (牌子) around. They are also expensive. But some experts say they are not much better than cheaper brands.

    For example, Jim Wilcox works for Consumer Reports. He tested all kinds of headphones. He says that $80 Koss Pro headphones provide basically the same quality (质量) and comfort as Beats. So why do people pay twice or even 10 times as much for the hottest brands?

    Experts say it's because fashionable, expensive brands send a message. Brands say “I belong” or “I can afford it.”

    Some people think that expensive brand names are worth the price. They say that some designer clothes really are top quality and that they last longer than cheaper brands. Some teenagers choose to wear popular brands because these brands make them feel good about themselves.

    Alexandra Allam, 17, likes to buy brand-name products. “I'd rather spend the extra money to get something I know I'll be satisfied with,” she says. Her friend Emmy Swan agrees, saying “As long as you can afford it, it seems reasonable to buy what you want.” But not all teenagers agree. “Spending hundreds of dollars for designer sunglasses is stupid and unreasonable,” says Daniel Steinbrecher, 16. “It's fake (假的) happiness.”

    People who are against wearing expensive brand names say that many designer brands aren't any better. “It's wasteful to buy things just because they are popular,” says Edmund Williams, 15. “You'll feel better if you buy things because you like them. If you have extra money to spend, it would be better to give it to people in need.”

2.给出一个算法的程序框图(见上),当输入的值为时,输出的结果恰好是
则“?“处的关系式是(    )

2.单选题(共6题)

3.
通过阅读课本,几个同学对生活中的圆周运动的认识进行交流.甲说:“ 洗衣机甩干衣服的道理就是利用了水在高速旋转时会做离心运动.” 乙说:“ 火车转弯时,若行驶速度超过规定速度,则内轨与车轮会发生挤压.” 丙说:“ 汽车过凸形桥时要减速行驶,而过凹形桥时可以较大速度行驶.” 丁说:“ 我在游乐园里玩的吊椅转得越快,就会离转轴越远,这也是利用了离心现象.” 你认为正确的是(  )
A.甲和乙B.乙和丙C.丙和丁D.甲和丁
4.
如图所示为洗衣机脱水筒.在匀速转动的洗衣机脱水筒内壁上有一件湿衣服与圆筒一起运动,衣服相对于圆筒壁静止,则(  )
A.衣服受重力、弹力、压力、摩擦力、向心力五个力作用
B.洗衣机脱水筒转动得越快,衣服与筒壁间的弹力就越小
C.衣服上的水滴与衣服间的附着力不足以提供所需要的向心力时,水滴做离心运动
D.衣服上的水滴与衣服间的附着力大于所需的向心力时,水滴做离心运动
5.
飞机俯冲拉起时,飞行员处于超重状态,此时座位对飞行员的支持力大于所受的重力,这种现象叫过荷.过荷过重会造成飞行员大脑贫血,四肢沉重,暂时失明,甚至昏厥.受过专门训练的空军飞行员最多可承受9倍重力的支持力影响.取g=10m/s2,则当飞机在竖直平面上沿圆弧轨道俯冲速度为100m/s时,圆弧轨道的最小半径为()
A.100mB.111mC.125mD.250m
6.
铁路在弯道处的内外轨道高度是不同的,已知内外轨道平面与水平面的倾角为θ,如图所示,弯道处的圆弧半径为R,若质量为m的火车转弯时速度小于.则(    )
A.内轨对内侧车轮轮缘有挤压
B.外轨对外侧车轮轮缘有挤压
C.这时铁轨对火车的支持力等于
D.这时铁轨对火车的支持力大于
7.
某公园里的过山车驶过轨道的最高点时,乘客在座椅里面头朝下,人体颠倒,若轨道半径为R,人体重为mg,要使乘客经过轨道最高点时对座椅的压力等于自身的重力,则过山车在最高点时的速度大小为()
A.0B.C.D.
8.
当汽车通过拱桥顶点的速度为10m/s时,车对桥顶的压力为车重的3/4,如果要使汽车在粗糙的桥面行驶至桥顶时,不受摩擦力作用,则汽车通过桥顶的速度应为( )
A.15m/sB.20m/sC.25m/sD.30m/s

3.多选题(共2题)

9.
在某转弯处,规定火车行驶的速率为v0.火车通过此处,下列有关说法中正确的是
A.当火车以速率v0行驶时,火车的重力与支持力的合力方向一定沿水平方向
B.当火车的速率v>v0时,火车对外轨有向外的侧向压力
C.当火车的速率v>v0时,火车对内轨有向内的挤压力
D.当火车的速率v<v0时,火车对内轨有向内侧的压力
10.
在图示光滑轨道上,小球滑下经平直部分冲上圆弧部分的最高点A时,对圆孤的压力为mg,已知圆弧的半径为R,则(  )
A.在最高点A,小球受重力和圆孤的压力
B.在最高点A,小球受重力和向心力
C.在最高点A,小球的速度为
D.在最高点A,小球的向心加速度为2g

4.解答题(共2题)

11.
“东风”汽车公司在湖北某地有一试车场,其中有一检测汽车在极限状态下车速的试车道,该试车道呈碗状,如图所示。有一质量为m=1t的小汽车在A车道上飞驰,已知该车道转弯半径R为150m,路面倾斜角为θ=45°(与水平面夹角),路面与车胎摩擦因数μ为0.25,求汽车所能允许的最大车速。
12.
如图,在公路转弯处,常采用外高内低的斜面式弯道,这样可以使车辆经过弯道时不必大幅减速,从而提高通行能力且节约燃料。若某处有这样的弯道,其半径为r=100m,路面倾角为θ,其横截面如图所示,且tanθ=0.4,取g=10m/s2

(1)求汽车的最佳通过速度,即不出现侧向摩擦力时的速度。
(2)若弯道处侧向动摩擦因数μ=0.5,且最大静摩擦力等于滑动摩擦力,求汽车的最大速度。
试卷分析
  • 【1】题量占比

    选择题:(2道)

    单选题:(6道)

    多选题:(2道)

    解答题:(2道)

  • 【2】:难度分析

    1星难题:0

    2星难题:0

    3星难题:0

    4星难题:0

    5星难题:0

    6星难题:2

    7星难题:0

    8星难题:5

    9星难题:3