Problem: Billy and Sally are brother and sister. Billy is seven and Sally is eight. Their mother, Deborah, likes to have Billy and Sally dress up in costumes and play a game where they are answering the telephone. Usually when they play the game, Billy answers the telephone in a loud voice, and Sally answers the telephone in a quiet voice. On Tuesdays, Billy answers in a quiet voice, and Sally answers in a loud voice. On Fridays, Billy answers in a loud voice and Sally in a quiet voice. Billy has blonde hair. Sally has brown hair. Deborah has blonde hair, and Billy and Sally's father, Bob, has brown hair. He tells them to eat lettuce every time that he sees them, so that they grow big and strong like he is. Deborah likes to add some sugar with the lettuce so that Billy and Sally know what it is like to have sweet tastes in their life. One day, a Wednesday, Billy throws some lettuce into Sally's hair. Deborah laughs an grabs some straw from their farm and puts it in Billy's hair. Billy and Sally live on a farm. They have a goat, named Joey, and a duck, named Quack. They sometimes play a game with the goat where they chase him around the farm. Other times, they play a game with Quack where they wave at Quack and laugh. They have a fun life growing up on the farm.

Question: "What game do Billy and Sally play with their goat?"

Answer: "Chase him around the farm"
Answer: yes

Problem: 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]

Question: "How does mass relate to weight?"

Answer: "Weight depends on mass"
Answer: yes

Problem: 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.

Question: "Do particles rubbed against a slippery surface move faster or slower?"

Answer: "Moving"
Answer:
no