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AP Physics · AP Chemistry · AP Biology

Pull in. Fix one topic. Get back out.

A short stop for AP science. Check what you know in one topic, fix the gaps, then get back to your practice questions.

Pick your course

Your board · 2.1 Systems and Center of Mass

2.1.A.1 Interactions set a system's properties Good
2.1.A.2 When a system counts as one object Fix
2.1.A.3 Energy and mass can cross the boundary Good
2.1.B.1 Center of mass lies on lines of symmetry Good
2.1.B.2 Calculating the center of mass Fix

Example from AP Physics 1: five of the nine ideas in topic 2.1. Read the two marked Fix, then Go.

Which AP course?

AP Physics 1

8 units · 43 topics · 537 questions

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2
3
4
5
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7
8

AP Physics 2

7 units · 46 topics · 736 questions

AP Physics C: Mechanics

7 units · 41 topics · 657 questions

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2
3
4
5
6
7

AP Physics C: Electricity and Magnetism

6 units · 31 topics · 552 questions

AP Chemistry

9 units · 91 topics · 847 questions

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2
3
4
5
6
7
8
9

AP Biology

8 units · 60 topics · 802 questions

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2
3
4
5
6
7
8

Not sure which physics course is yours? Physics 1, 2, or C: how they differ.

How a stop works

Check
One question for each idea in the topic. Your board shows what to fix.
Fix
Short sections, one per idea, with the mistakes students most often make.
Go
The rest of the questions, each explained as soon as you answer. Then back to your practice.

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