QUICK REVIEW
Quick Review — Drawing and Solving Free-Body Diagrams — Calculus-Based
Refresh the essential ideas and relationships for Drawing and Solving Free-Body Diagrams in just a few minutes.
TIME
5–10 minutes
BEST FOR
A rapid refresh
FINISH WITH
Key ideas refreshed
After this quick review, you'll be able to...
recall the essential ideas and decide what to review next.
Choose how you want to review
Course Alignment
This Physics Sensei Topic Review is an independent learning resource. Use it to reinforce key concepts, prepare for homework, or review before a quiz or exam.
Related Unit Review: If you need to review the complete unit material, review Newton's Laws and Free-Body Diagrams here →
RESOURCE: Physics Sensei Topic Review | TOPIC ID: MEC-U05-T02 | TOPIC: Drawing and Solving Free-Body Diagrams | PARENT UNIT: MEC-U05 — Newton's Laws and Free-Body Diagrams | COURSE LEVEL: Calculus-Based Physics
BEST USED ✓ After learning the topic ✓ Before starting homework ✓ Before a quiz or exam
Your Review Plan
Complete these four stages to quickly refresh the essential ideas and confirm you're ready to continue.
4 Stages • Approximately 5–10 minutes.
Quick Recall
Let's quickly refresh what you already know. These short recall activities will help you bring the most important ideas back to mind before reviewing them.
QUICK RECALL
Recall Activity
Complete the three statements from memory before revealing the answer.
Sketch an FBD for a box on a horizontal floor that is pushed to the right. Name every force acting on the box.
Reveal Answers
Weight downward, normal force upward, applied force right, and friction left.
Why it works: The FBD contains forces acting on the chosen box only.
Ready to refresh the essentials?
Great! Now let's review the most important ideas you'll want to remember.
Essential Idea
Take one last look at the most important concept from this topic. If you remember this idea, the rest will come back much more easily.
ESSENTIAL IDEA
Isolate One Object
ESSENTIAL IDEA Model the System Before Writing Equations An FBD is a force model of one selected body. Include every external force on that body and exclude forces the body exerts on other objects. Distinguish contact forces (normal, friction, tension) from long-range forces such as weight.
ΣF = ma
Example: For a crate pulled across a floor, the FBD can include weight, normal force, applied force, and friction.
Sensei note: Newton's third-law partner of a force acts on another body, so it does not belong on the same FBD.
Ready to check your memory?
You've refreshed the essential idea. Now see how much you remember before moving on. Need a quick reminder?
Confidence Check
You've refreshed the essential ideas. Now answer this quick confidence check to confirm you're ready to move on.
CONFIDENCE CHECK
From Diagram to Equation
Answer all three without notes.
Use the FBD information to find the requested quantity. A 5.0 kg box has a 20 N force to the right and 8 N of friction to the left. What is its horizontal acceleration?
Reveal Answers
ΣFₓ = 20 − 8 = 12 N; aₓ = 12/5.0 = 2.4 m/s² to the right.
Why it works: Sum signed force components along the chosen x-axis before applying Newton’s second law.
Ready for your next step?
Great work! You've refreshed the essential ideas. Now choose the resource that best matches what you'd like to do next. Need a quick reminder?
Next Step
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