You know that friction also causes heat. Think about when you rub your hands together. It is friction that makes them warm. But why does this happen? Friction causes the molecules on rubbing surfaces to move faster. Faster moving particles have more heat energy. Heat from friction can be useful. Can you think of other places where you might find friction? Friction also lets you light a match. Heat from friction can also cause problems. It can cause a car to overheat. To reduce friction, oil is added to the engine. Oil coats the surfaces of moving parts. This coating of oil makes them slippery. When things are slippery there is less friction. Have you ever seen a sign that says, slippery when wet? This too has to do with friction. Water, like oil, can reduce friction. The wet surface may allow your shoes to slide more easily.
What question would one ask from this paragraph?
Answer: What would happen if all the oil leaked out of a running car engine?

It is not enough to describe some objects by their location. We may also need to know its direction. For example, a wind blows a storm over your school. Where is that storm coming from? Where is it going? How can we describe a direction? The most common way is by using a compass. A compass is a device with a floating needle (Figure 2.1). The needle is a small magnet. The needle aligns itself with the Earth's magnetic field. The compass needle always points to magnetic north. If you have a compass and you find north. You can then know any other direction. See the directions, such as east, south, west, etc., on a compass rose. The Earth has two poles. It has a magnetic north pole. It also has a geographic north pole. These two poles are close to each other but not the exact same place.
What question would one ask from this paragraph?
Answer: What is a compass?

Tommy and Suzy (brother and sister) went to the playground one afternoon with their mom and dad, Jan and Dean. They were playing a game of tag and having the best time ever running after each other and laughing. They liked to play tag instead of building sandcastles or swinging. They liked tag because they liked to run. They like to play hopscotch or jump rope but that day they wanted to play tag. Other games aren't as fun. They met Tony and Ally (who are best friends) and invited them to play tag too. Tony and Ally like to play other games like hopscotch or jump rope but that day they joined the game of tag. Making new friends is important. Tony and Ally would rather make friends than play their favorite games.
What question would one ask from this paragraph?
Answer: What were the four names of the children that played on the playground?

Electric charge is a physical property. It occurs between particles or objects. It causes them to attract or repel each other. They do not even have to touch. This is unlike the typical push or pull you may be familiar with. All electric charge is based on the protons and electrons in atoms. A proton has a positive electric charge. An electron has a negative electric charge. Forces on Charged Objects Most atoms are balanced electrically. They have the same number of positive and negative charges. Therefore, the number of protons equals the number of electrons. Neutrons do not matter as they have no charge. When an object loses some electrons, it becomes positively charged. There are now more protons than electrons inside the atom. The lost electrons may remain free. Or, they may attach to another object. The new object now has more electrons than protons. It then becomes negatively charged.
What question would one ask from this paragraph?
Answer:
If a particle loses some of its protons, what is the particle's charge?