QUES: An atom is the very smallest particle that still the elements properties. All the atoms of an element are alike. They are also different from the atoms of all other elements. For example, atoms of gold are always the same. It does not matter if they are found in a gold nugget or a gold ring. All gold atoms have the same structure and properties. For example, all gold atoms contain 79 protons. One of golds unique properties is that it is a great conductor of electricity. Gold is a better conductor of electricity than copper. Gold is more rare and expensive than copper. Copper is used in house wiring. Gold is far too expensive.
Do you have any questions?
MY QUESTION: How is gold different from copper?

QUES: The cute red ball rolled over to the blue ball and said hello. The blue ball was scared and went to cry to the green ball. The green ball laughed at the blue ball. Then the green ball told the orange ball that blue ball was stupid. Most felt this was not good to do and so they punished the green ball by taking away all his air. From that day on everyone saw the air-less green ball and knew that they could not do or say any bad things. This is how the trouble started. The purple ball used the fear of everyone to become the leader that they all feared. The purple ball was mean to everyone. Until one day the red ball spoke up and got all the other colored balls together and they took the air from the purple ball and put it in the green ball. Sadly, the green ball had been without air for too long and was dead.
Do you have any questions?
MY QUESTION: Why did the green ball laugh at the blue ball?

QUES: Magnets are able to place a force on certain materials. This force is called a magnetic force. The force a magnet exerts is a little different from the forces you may normally think about. You exert a force on a book when you lift it. You also exert a force on the pedals of your bicycle. In both those cases, those forces cause a change. The change you see in both these cases is called motion. Magnets, too, can produce change. They can produce motion just like you do. Unlike you, magnets do not have to touch something to exert a force. A magnetic force is exerted over a distance. Thats right, a magnet can push or pull certain items without ever touching them. Thats how the maglev train works. Do you know another type of force that does not require objects to touch? These forces are known as non-contact forces. Another type of non-contact force you may be familiar with is gravity. Gravity too can cause changes in motion. Gravity holds our moon in orbit without touching it.
Do you have any questions?
MY QUESTION: How do magnets exert force?

QUES: If you have a mass of 50 kg on Earth, what is your weight in newtons? An object with more mass is pulled by gravity with greater force. Mass and weight are closely related. However, the weight of an object can change if the force of gravity changes. On Earth, the force of gravity is the same everywhere. So how does the force of gravity change? It doesnt if you stay on Earth. What if we travel to another planet or moon in our solar system? Look at the photo of astronaut Edwin E. Aldrin Jr. taken by fellow astronaut Neil Armstrong in the Figure. They were the first humans to walk on the moon. An astronaut weighs less on the moon than he would on Earth. This is because the moons gravity is weaker than Earths. The astronauts mass, on the other hand, did not change. He still contained the same amount of matter on the moon as he did on Earth. If the astronaut weighed 175 pounds on Earth, he would have weighed only 29 pounds on the moon. If his mass on Earth was 80 kg, what would his mass have been on the moon? [Figure 3]
Do you have any questions?
MY QUESTION:
Why did Edwin E. Aldrin Jr. and Neil Armstrong weigh less on the moon?