Problem: What if two children push a swing at the same time? Would the swing go higher? Yes, together their force would be more. It is common for forces to be combined. Most objects on Earth have at least two forces acting on them. Do you know what one of them is? Of course, that force is gravity. How many forces do you have on you right now? Gravity pulls you down toward the center of Earth. Your legs exert a downward force. They hold you up against the pull of gravity. Consider the example in Figure 1.3. A book is resting on a table. Gravity pulls the book downward. It has a force of 20 newtons. At the same time, the table pushes the book upward. Its force is also 20 newtons. The table opposes the pull of gravity.

Question: "How many forces do you have on you right now?"

Answer: "3"

OPTIONS:
- no
- yes
Answer: no

Problem: The factory is highly automated and designed to shift flexibly to produce many different kinds of chips to suit demand. "The diversity is the big difference with this plant," said Richard Doherty, president of Envisioneering, a research firm. "It gives IBM the capability to make so many different kinds of custom chips, and the world is going to custom chips." The 140,000-square-foot plant is a testament to advanced manufacturing technology. The 300-millimeter silicon wafers -- about the size of a standard pizza -- are shuttled around the facility in enclosed plastic pods, which ride on overhead tracks. They drop down from wires automatically into machines, sheathed in stainless steel and glass, for each stage of processing and fabrication. Throughout the 500 processing steps, which typically last 20 days, the wafers are not touched by human hands. The circuits etched into the chips are less than one thousandth the width of a human hair. Human operators are there to monitor the systems, catch errors and fine-tune the production process for maximum efficiency. Because each of the hundreds of processing machines is self-enclosed, and essentially airtight, the uniforms operators wear are less constricting than in the previous generation of chip plants, which looked like space suits. The operators at the East Fishkill factory wear light nylon uniforms, light blue shoe coverings and translucent hair nets made of paper. They look more like workers in a bakery. Yes, said Richard Brilla, director of the new facility, "but the donuts are a lot more costly here." Each wafer, holding hundreds of chips, is worth $6,000 to $10,000 apiece, depending on what insulation, circuitry and materials are used.

Question: "What is the name of the factory where Richard Brilla is a Director?"

Answer: "East Fishkill factory"

OPTIONS:
- no
- yes
Answer: yes

Problem: 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.

Question: "What kind of charge does a particle with more protons than electrons have?"

Answer: "Positive charge"

OPTIONS:
- no
- yes
Answer:
yes