「課外練習」國外大學初階物理題(英文版本)

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以下是取錄自MIT,Classical Mechanics

A bucket of water is swung in a vertical plane at the end of a rope of length  [size=124%]l=8  m. The mass of the bucket plus water is 5 kg and the gravitational acceleration is g=10m/s^2. We assume that the mass of the rope can be neglected.

(a) What is the minimal speed of the bucket at its highest point in the circular motion, such that the water does not fall out? (in m/s)
v=?


(b) For this speed, what is the magnitude of the centripetal acceleration that the water in the bucket experiences at the highest point? (in m/s^2)
[size=124%]ac=?

(c) At the lowest point,

a:the speed is higher and the centripetal acceleration is lower than at the highest point of the circular motion.
b:the speed is lower and the centripetal acceleration is higher than at the highest point of the circular motion.
c:the speed is higher and the centripetal acceleration is higher than at the highest point of the circular motion.
d:the speed is lower and the centripetal acceleration is lower than at the highest point of the circular motion.
e:speed and centripetal acceleration are the same as at the highest point of the circular motion.

以下是取錄自Stanford university

The significance of the battery, invented around 1800, was that:

a:It provided the possibility of sustained electric current.
b:It inspired James Clerk Maxwell to develop his theory of electromagnetism.
c:It opened up the possibility of wireless communication via electromagnetic waves.
d:It inspired Thomas Young to develop his wave theory of light.

“Electromagnetic induction” refers to the phenomenon of:

a:How a changing magnetic field can generate an electric current in a wire.
b:How electric current traveling through a wire can induce the wire to glow.
c:Using mechanical models to portray how electromagnetism works.
d:Electromagnetic waves traveling at the speed of light.

Which two technologies had a symbiotic relationship?

a:The railroad and the electric battery.
b:The railroad and the telegraph.
c:The electric light and radio.The telegraph and the electric light.


Einstein’s father and uncle were involved in what type of business?

a:Electric power and lighting.
b:Railroads.
c:Radio.
d:Clockmaking and timekeeping.


Who demonstrated experimentally that electromagnetic waves exist?

a:Michelson and Morley.
b:James Clerk Maxwell.
c:Thomas Young.
d:Heinrich Hertz.


What was mentioned as a surprising source for gaining insight into how the British and French had different styles of doing physics in the late 1800s?

a:Journal articles.
b:Newspaper articles.
c: Lectures broadcast on radio.
d: Obituaries.


What was the goal of the Michelson-Morley experiment?

a:To demonstrate the commercial feasibility of incandescent lighting.
b:To prove that light is an electromagnetic wave.
c:To detect the influence of an “ether wind” on the velocity of light.
d:To prove that electromagnetic waves exist.

待續,將會加入加州理工學院(CIT)和喬治城理工學院(GIT)的物理練習