GED and HiSET science — earth and space science

Earth and space science is the strand where almost everyone arrives carrying a confident wrong answer, usually learned young and never examined since. This set is built around that fact: in several of the twelve, the tempting option is the famous misconception, and the explanation says why it is tempting before it says why it fails.

The seasons are the clearest case. It is July, the northern hemisphere is in summer and the southern in winter, and the offered explanation is that the earth is closer to the sun. It is not the cause — and the reason the answer is wrong is visible in the question itself, since one earth cannot be near and far at once for two hemispheres. The moon's phases are the second: not the earth's shadow, which is an eclipse, but the changing angle from which we see a half-lit ball. The tides are the third, where the puzzle is not why there is a high tide but why there are two, on opposite sides of the planet.

Then the parts of the subject that are about reading a situation. A boundary where two plates converge and one is driven under the other, which is what makes the earthquakes. A rock traced through a sequence — buried, heated, melted, cooled — and asked to name the types it passed through. A boulder split by ice and a slab carried off by meltwater, one of which is weathering and the other erosion. Rain running off a paved street and soaking into a wooded slope. A cliff where the fossil in the lower layer is older than the one above it, provided the layers have not been turned over since, which is the assumption the rule quietly makes.

Two items are about how a claim is tested. A city has its coldest week in thirty years and someone offers that as proof the climate is not warming: one week is weather, and the distribution it came from is measured in decades. And a village pumps an aquifer that rainfall refills at a hundred million gallons a year — renewable at sixty million a year, not renewable at a hundred and eighty, because renewable describes a rate and not a substance.

The quiz has no notation: every number is in words and digits inside its own question, and the question about rock layers comes with a simple drawing of the cliff, as such questions do on the real tests. A few flashcards and written items carry a simple drawing too.

Zestly is an independent study tool. It is not affiliated with GED Testing Service, which owns the GED test, or with the HiSET program, and it is not a test center.

• Explain the seasons by axial tilt, and say why distance from the sun cannot be the cause
• Say what produces the moon's phases, and what the earth's shadow actually produces
• Explain why a coast gets two high tides a day rather than one
• Describe what happens where two plates converge, and trace a rock through the rock cycle
• Tell weathering from erosion in a case where both occur
• Explain why rain runs off pavement and soaks into a wooded slope, and how the greenhouse effect traps heat
• Apply the principle of superposition, and state the assumption it depends on
• Separate weather from climate when a single cold spell is offered as evidence, and judge renewability by comparing rates

Practice material written by Zestly; the quiz has no diagrams and all figures are in words. From the bank: "A village draws its drinking water from an aquifer that rainfall refills at a rate of about 100 million gallons a year. For decades the village pumped about 60 million gallons a year. A new food plant has raised that to 180 million gallons a year. Is the aquifer a renewable resource?" The answer has to come from the two numbers, not from the word "water".