2022知到答案 University physics 最新完整智慧树知到满分章节测试答案

第一章 单元测试

1、 问题:How many years older will you be 1.00 gigaseeond from now? (Assume a 365-day year.) （ ）
选项：
A:41.7 y
B:31.7y
C:51.7 y
D:21.7 y
答案: 【
31.7y
】

2、 问题:Scientific notation:

3 3.610+230= ´ ？ （ ）
选项：
A:

3 4.810 ´
B:

3 2.810 ´
C:

3 3.810 ´
D:

3 1.810 ´
答案: 【

3 3.810 ´
】

3、 问题:

In Δ ABC, we know that D is a point on the extension line of BC, and E is the midpoint of line segment AD. If , and , then x = （ ）.

选项：
A:−1/4
B:1/4
C:−1/3
D:1/3
答案: 【
−1/4
】

4、 问题:

Vector operation. If , and , find the value of , such that the vectors and will be perpendicular to each other （ ）.

选项：
A:-2/3
B:-5/3
C:-4/3
D:-8/3
答案: 【
-4/3
】

5、 问题:

Two displacement vectors,  and , have magnitudes S=3 m and T=4 m, which of the following could not be the magnitude of the difference vector? (There may be more than one correct answer.) （　   　）.

选项：
A:9 m
B:7 m
C:5 m
D:1 m
答案: 【
9 m
】

第二章 单元测试

1、 问题:A particle is moving straight along the x direction, and its position is determined by the equation , where the unit of x is meter, and the unit of t is second. Then its velocity is expressed as （ ）
选项：
A:v=20t
B:v=20t+8
C:v=10t
D:v=10t+8
答案: 【
v=20t
】

2、 问题:Velocity is a vector, and speed is also a vector. （ ）
选项：
A:对
B:错
答案: 【
错
】

3、 问题:The magnitude of the acceleration of the object may be very large, while the magnitude of the velocity of an object can remain unchanged. （ ）
选项：
A:对
B:错
答案: 【
对
】

4、 问题:A warship fires the shells at tow enemy ships at the same time. It is known that the shells will fly along the parabolic orbits as shown in the figure and hit the enemy ships, assume the shells has the same initial speed, which ship will be hit first? （ ）
选项：
A:Ship A
B:Ship B
C:Both ships will be hit at the same time
D:More information is needed
答案: 【
Ship B
】

5、 问题:A car moves at constant speed in a horizontal of radius 20.0 m, making a complete circle in 7.0 s. What is the acceleration of the car? （ ）
选项：
A:

2 16.1 / ms
B:

2 21.4 / ms
C:

2 18.5 / ms
D:

2 11.2 / ms
答案: 【

2 16.1 / ms
】

第三章 单元测试

1、 问题:Suppose an astronaut landed on a planet where g=19.6 m/s². Compared to earth, would it be for her to catch a ball that is moving horizontally at 12 m/s? (Assume that the astronaut’s spacesuit is a lightweight model that doesn’t impede her movements in any way.) （ ）
选项：
A:easier
B:harder
C:just as easy
D:More information is needed to determine
答案: 【
just as easy
】