No atoms are destroyed or created. The bottom line is: Matter cycles through the universe in many different forms. In any physical or chemical change, matter doesn't appear or disappear. Atoms created in the stars (a very, very long time ago) make up every living and nonliving thing on ...
Non-ionizing radiation is relatively low-energy radiation that doesn't have enough energy to ionize atoms or molecules. It's located at the low end of the electromagnetic spectrum. Non-ionizing radiation sources include power lines, microwaves, radio waves, infrared radiation, visible light and las...
After all, many of us humans like to have one right answer. But Einstein paved the way in 1905 by embracing wave-particle duality. We've already discussed the photoelectric effect, which led Einstein to describe light as a photon. Later that year, however, he added a twist to the story...
One reason many people oppose nuclear power is because they think nuclear plants are like enormous nuclear bombs, just waiting to explode and wipe out civilization. It's true that nuclear plants and nuclear bombs are both based on nuclear reactions in which atoms split apart, but that's genera...
After all, many of us humans like to have one right answer. But Einstein paved the way in 1905 by embracing wave-particle duality. We've already discussed the photoelectric effect, which led Einstein to describe light as a photon. Later that year, however, he added a twist to the story...
How can scientists search for strange matter if no one's ever seen it? Well, they actually do know what bits of strange matter would look like on Earth if it weren't dangerous. It would resemble our regular atoms -- a positively charged core made of quarks, with electrons around -- on...
Many scientists believe the universe may have reached an unfathomable size, and that humans will never see its end. However, this does not mean that there is not a limit to the size of the universe. It might simply have been designed without a boundary. Hence, the question of “Is this...
After that, atoms began to form and⑥in all directions(=in every direction)朝四面八方combine to create stars and other bodies.※that threw matter..是 that引导的定语从句,修饰 a“BigFor several billion years after the “ BigBang”。Bang", the earth was still just a cloud of dust.⑦atom/...
Whether or not they have wings, some insects might get the chance to fly if selected to go in space and become part of the space-farming research. Though many plant parts are inedible for humans, they make a delicious meal for insects. Insects can convert much of this inedible material in...
And that was just the first spacecraft of many to orbit, flyby and even land on the Martian surface. So what have scientists learned about Mars from the data gleaned from these missions? And when might the machines on Mars get human company? Will humans ever set foot on the Red Planet...