Assignment:
Part 1
• In what sense does the moon fall?
• How does the force of gravity between two bodies change when the distance between them is tripled?
• Would the springs inside a bathroom scale be more compressed or less compressed if you weighed yourself in an elevator that accelerated upward? Accelerated downward? Would the springs inside a bathroom scale be more compressed or less compressed if you weighed yourself in an elevator that moved upward at a constant velocity? In an elevator that moved downward at constant velocity?
• Explain why occupants of the International Space Station are firmly in the grip of Earth's gravity, even though they have no weight.
• A stone is thrown up at an angle. Neglecting air resistance, what happens to the horizontal component of its velocity along its trajectory? The vertical component?
• A projectile is launched vertically at 100 m/s. If air resistance can be neglected, at what speed does it return to its initial level?
• What happens to an object close to Earth's surface if it is given a speed exceeding 11.2km/s?
Part 2
• Distinguish between force and pressure.
• How does the pressure exerted by a liquid change with depth of the liquid?
• Why does buoyant force act upward on an object submerged in water?
• How does the buoyant force on a fully submerged object compare with the weigh of the water displaced?
Part 3
• What are the temperatures for freezing water and boiling water on the Kelvin temperature scale?
• In which direction does thermal energy flow between hot and cold objects?
• How does heat differ from thermal energy?
• How is the energy value of food determined?
Part 4
• What is the role of "loose" electrons in heat conductors?
• Describe how heat is transferred by convection
• What kind of objects give off radiant energy?
• What are the four common phases of matter, and what are the processes which transform one to another?
• Does a gas give off energy or absorb energy when it changes to a liquid? How about a solid changing into a liquid?
Part 5
• Distinguish between an atom and an element.
• Distinguish between atomic number, mass number, and atomic mass.
• What happens to the properties of elements across any period of the periodic table?
• What causes an atom to emit light?
• What was Planck's quantum hypothesis?
Part 6
• What does "radioactive" mean?
• Describe the three types of radioactive radiation: alpha, beta, and gamma.
• Why doesn't the repulsive electric force of protons in the atomic nucleus cause the protons to fly apart?
• What is meant by the half-life of a radioactive sample?
• Why is there more carbon-14 in living bones than in once-living ancient bones of the same mass?
• How is a nuclear reactor similar to a conventional fossil-fuel power plant? How is it different?
• Who discovered that energy and mass are two different forms of the same thing?
• What kind of nuclear power is responsible for sunshine?
Part 7
• How many electrons can occupy the first shell? How many can occupy the second shell?
• How do the electron-dot structures of elements in the same group in the periodic table compare with one another?
• How does an ion differ from an atom?
• Why does the fluorine atom tend to gain only one electron?
• Which elements tend to form ionic bonds?
• Do metals more readily gain or lose electrons?
• Which elements tend to form covalent bonds?