【题目】A Light(光) travels very fast. It moves at a speed of 300, 000 kilometers a sccond(秒). Light reaches us from the moon in less than one and a half seconds. The moon is about 382,000 kilometers away from the earth.Light from the sun gets to us in 8. 5 minutes. It'...
Light from the nearest star reaches us in about four years. When you look at a star, you do not see its present condition. You see it as it used to be. Light from some stars takes hundreds of years to reach us. We never see a star as it is now. We see it as it was long a...
Speed of Light: Light moves at a definite speed of3×108m/s. It was first predicted that light is an electromagnetic wave which is the simultaneous and synchronized oscillations of electric and magnetic fields. Later it was found that light also has particle nature and is composed of photons...
Mick Moves at Speed of Light
Today we know that light moves at a definite speed of around 299,792 kilometers per second in vacuum. This value has been measured using advanced technology and methods which have been devised using years of research and experience. Earlier there were different methods used to measure the speed...
It moves at a speed(速度) of 300, 000 kilomcters(千米) a second. Light reaches(=gets to) us from the moon in less than a second and a half. The moon is almost 382, 000 kilometers away. The sun is about 149,840,000 kilomcters away from the carth. The other stars are farther...
Light travels at a speed (速度) which is about a million times faster than that of sound. In one second, light travels about 300,000 kilometers, but sound travels only 340 meters. You can get some idea of this difference by watching the start of a running match. If you stand quite ...
So, what is the speed of light? Light moves at an incredible 186,000 miles per second (300,000 kilometers per second), equivalent to almost 700 million mph (more than 1 billion km/h). That's fast enough to circumnavigate the globe 7.5 times in one second, while a typical passenger...
【题目】Light travels at a speed which is about a million times faster than the speed of sound. In one second, light travels about 300,000 km, but sound travels only 344m. You can get some idea of this difference by watching the start of a race. If you stand some distance away from...
(3)A (4)C 【解析】本文是一篇说明文,作者介绍了光的传播速度要远远高于声的传播。本文描述了一种奇怪的自然现象,引起了人们的思考。 (1)考查细节理解。根据第一段中的“Light travels at a speed which is about a million times faster than the speed of sound.”可知光的传播速度比声音的传播速度要快一...