1.单选题- (共6题)








A.控制卫星从图中低轨道进入椭圆轨道需要使卫星减速 |
B.卫星在近地轨道与远地轨道运动的速度之比为![]() |
C.卫星从![]() ![]() ![]() |
D.卫星在近地轨道通过![]() ![]() |

A.若只闭合电键S 时,V1的示数一定不变、V2的示数一定变小 |
B.若只闭合电键S 时,A1、A2和 A3 的示数一定都变大 |
C.若只增加原线圈匝数 n1,R1消耗的功率一定变大 |
D.若只增加原线圈匝数 n1,变压器输入功率一定变大 |

A.![]() | B.![]() | C.![]() | D.![]() |


A.电阻R中没有感应电流
B.电阻R中的感应电流方向由a至b
C.穿过闭合回路的磁通量变化率为零
D.穿过闭合回路的磁通量变化率为一非零常量

A.![]() | B.![]() | C.![]() | D.![]() |


A.当线圈平面与磁感线平行时,线圈中电流强度为零 B.电流有效值 ![]() |
B.外力做功的平均功率![]() |
C.当线圈平面与磁感线平行时开始转动![]() ![]() |
2.选择题- (共2题)
阅读理解
A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.
“It's extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components. “The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.
They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.
While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers' fields or on the battlefield. “Basically it should be able to take off, land and fly around,” he said.
Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”
3.多选题- (共5题)

A.水平平地面对斜面体C的支持力减小 |
B.轻质细绳对物块B的作用力不变 |
C.斜面体C对物块B的摩擦力一直增大 |
D.水平地面对斜面体C的摩擦力一直增大 |

A.A 球的速度最大时,角BOA 的角平分线在竖直方向 |
B.A 球的速度最大时,A 球在其运动圆周的最低点 |
C.A 球的速度最大时,两小球的重力势能之和最小 |
D.A 球的速度最大时,B 球在其运动圆周的最高点 |

A.物块与弹簧组成的系统机械能的增加量为 (qE - mmg)L2 |
B.物块电势能的减少量等于弹簧弹性势能的增加量与系统产生的内能之和 |
C.物块的速度最大时,弹簧的弹性势能为 (qE - mmg )L1- ![]() |
D.若物块能弹回,则向右运动过程中经过A 点时速度最大 |

A.小球由静止沿棒竖直下落的最大加速度为 2m/s2 |
B.小球由静止沿棒竖直下落最大速度 2m/s |
C.若磁场的方向反向,其余条件不变,小球由静止沿棒竖直下落的最大加速度为 5m/s2 |
D.若磁场的方向反向,其余条件不变,小球由静止沿棒竖直下落的最大速度为 45m/s |

A.金属线框刚进入磁场时感应电流方向沿adcba方向 |
B.金属线框的边长为v1(t2-t1) |
C.磁场的磁感应强度为![]() |
D.金属线框在0 - t4的时间内所产生的热量为![]() |
4.解答题- (共3题)

(1)小物块与小车BC 部分间的动摩擦因数;
(2)小物块从A 滑到C 的过程中,小物块获得的最大速率.


(1)求极板间电场强度的大小;
(2)若粒子运动轨迹与小圆相切,求Ⅰ区磁感应强度的大小;
(3)若Ⅰ区、Ⅱ区磁感应强度的大小分别为



(1)物体下落过程的最大速度vm;
(2)物体从静止开始下落至速度达到最大的过程中,电阻R 上产生的电热Q;
(3)物体从静止开始下落至速度达到最大时,所需的时间t。
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【1】题量占比
单选题:(6道)
选择题:(2道)
多选题:(5道)
解答题:(3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:3
5星难题:0
6星难题:11
7星难题:0
8星难题:0
9星难题:0