PMA 2 Review (Comp Science 2)

PMA 2 Review (Comp Science 2)

Multiple Choice

Which sentence best describes a scientific theory?

• It is well-tested and explains a wide range of observations on why the natural world works.

• It can be proven conclusively, because it is how the natural world works.

• It can never change, because it is how the natural world works.

• It can never change, because it is why we think the natural world works.

Multiple Choice

What is the difference between a scientific theory and a scientific law?

• A theory is a well-tested explanation of why the natural world works and a law is a concrete physical representation (model).

• A theory is a well-tested description of how the natural world works and a law is a well-tested explanation of why the natural world work.

• A theory is a well-tested explanation of why the natural world works and a law is a well-tested description of what happens in the natural world.

• A theory is a hypothesis that is yet to be proven false and a law is a hypothesis that will always be true.

Multiple Choice

In 1897, Joseph Thomson discovered that atoms contain electrons. He proposed a change in the atomic theory of that time, and the theory was changed because of his discovery. Since Thomson’s discovery, atomic theory has been changed again. What is the best explanation for why scientific theories are changed?

• Theories more than ten years old are usually out of date.

• New evidence that supports a change causes scientists to change earlier theories.

• Scientists want to prove that the work of other scientists is wrong.

• So much information is available today that it is harder to focus research and disprove theories.

Multiple Choice

Mai tells Jaz her theory about why sea turtles nest on the beach instead of in the ocean. She says, “The turtle eggs would sink to the bottom of the ocean, and the baby turtle would drown.” Mai says her uncle, a fisherman, told her this information. Jaz tells Mai that her theory is not scientific. Why does Mai’s idea not meet the requirement to be a scientific theory?

• Mai’s idea is already a scientific law.

• Mai’s idea is a good guess that can be tested by experiments.

• Mai and her uncle are not scientists.

• Mai’s idea is not supported by scientific evidence.

Multiple Choice

Waves transfer:

• water

• energy

• wind

• particles

Multiple Choice

If you can not see through an object, in other words, light does not pass through, it is:

• transparent

• opaque

• translucent

• solid

Multiple Choice

This type of material allows most light to pass trough but forms a blurry image, like looking through a fogged up window.

• opaque

• transparent

• translucent

• echo

Multiple Choice

Sound waves are __________ waves that can only travel through __________.

• transverse, air

• transverse, matter

• longitudinal, liquids

• longitudinal, matter

Multiple Choice

Sound waves can travel through a vacuum or empty space.

• True

• False

Multiple Choice

Which statement best define a wave medium?

• The material through which a wave travels.

• The distance from one wave crest to the next.

• A point half way between the crest and trough.

• The speed at which waves travel in water.