1.选择题- (共4题)
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Eyesight plays avery important role in our daily life. Every waking moment, the eyes are working to see the world around us. Over forty percent of Americans worry about losing eyesight, but it's easy to include steps into our daily life to ensure healthy eyes. Here are five suggestions for a lifetime of healthy eyesight:
•Schedule yearly exams.{#blank#}1{#/blank#}Experts advise parents to bring babies 6 to 12 months of age to the doctor for a careful check. The good news is that millions of children now can have yearly eye exams and following treatment, including eyeglasses.
•Protect against UV rays(紫外线).Longterm stay in the sun creates risk to your eyes. No matter what the season is, it's extremely important to wear sunglasses.{#blank#}2{#/blank#}
•Give your eyes a break. Twothirds of Americans spend up to seven hours a day using computers or other digital products.{#blank#}3{#/blank#} Experts recommend that people practice the 20/20/20 rule: every 20 minutes, take a 20second break and look at something 20 feet away.
•{#blank#}4{#/blank#}As part of a healthy diet, eat more fruits and vegetables each day. Vitamins(维生素) C and E help protect eyesight and promote eye health.
•Practice safe wear and care of contact lenses(隐形眼镜).Many Americans use contact lenses to improve their eyesight. While some follow the medical guidance for wearing contact lenses, many are breaking the rules and putting their eyesight at risk.{#blank#}5{#/blank#} Otherwise, you may have problems such as red eyes, pain in the eyes, or a more serious condition.
A.Eat your greens.
B.Eye care should begin early in life.
C.They can properly protect your eyes.
D.Stay in good shape by taking more Vitamins.
E.Parents usually don't care about their own eyesight.
F.Always follow the doctor's advice for appropriate wear.
G.This frequent eye activity increases the risk for eye tiredness.
2.多选题- (共4题)

A.圆环,弹簧和地球组成的系统机械能不守恒 |
B.弹簧的弹性势能先增大后减小 |
C.弹簧的弹性势能增大了![]() |
D.弹簧的最大压缩量小于其最大伸长量 |
A.机械波和电磁波都能在真空中传播 |
B.铁路,民航等安检口使用红外线对行李内物品进行检测 |
C.根据狭义相对论的原理知,在不同的惯性参考系中,一切物理规律都是相同的 |
D.两列波叠加时产生干涉现象,其振动加强区域与减弱区域是稳定不变的 |


A.A | B.B | C.C | D.D |




A.电压表V的示数为22V |
B.当![]() |
C.当![]() |
D.当![]() ![]() |
3.填空题- (共1题)


4.解答题- (共2题)


(1)碰撞前瞬间A的速率v。
(2)碰撞后瞬间A与B整体的速度。
(3)A与B整体在桌面上滑动的距离L。

(1)若k=1,求匀强电场的电场强度E;
(2)若2<k<3,且粒子沿水平方向从S2射出,求出粒子在磁场中的速度大小v与k的关系式和Ⅱ区的磁感应强度B与k的关系式.
5.实验题- (共1题)
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【1】题量占比
选择题:(4道)
多选题:(4道)
填空题:(1道)
解答题:(2道)
实验题:(1道)
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【2】:难度分析
1星难题:0
2星难题:0
3星难题:0
4星难题:2
5星难题:0
6星难题:6
7星难题:0
8星难题:0
9星难题:0