question

Name ___________________

Ch. 4 – 7, 12 – 13, 15 HW

Ch. 4

· 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?

Ch. 5

· 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?

Ch. 6

· 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?

Ch. 7

· 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?

Ch. 12

· 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?

Ch. 13

· 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?

Ch. 15

· 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?