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Axleroads lessonpage b

Axle Roads

How do vehicles turn so smoothly?

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Axle Roads

How do vehicles turn so smoothly?

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Axleroads lessonpage b
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How do vehicles turn so smoothly? When a car makes a U-turn, the outer wheel travels farther than does the inner wheel. So why doesn’t the car feel jerky?

In this lesson, students calculate the circumferences of circles to determine how far vehicles travel during a turn and explore the engineering that allows cars to turn so smoothly.

REAL WORLD TAKEAWAYS

  • A turning radius describes the smallest circle a car can make. The smaller the radius, the tighter the turn.
  • Left and right car wheels have to cover different distances – and thus rotate different numbers of times – when turning. A differential axle allows this to happen.

MATH OBJECTIVES

  • Calculate the circumference of a circle
  • Model with geometry to solve real-world problems

Appropriate most times as students are developing conceptual understanding.
Lesson gauge medium
Grade 7
Measuring Circles
Lesson gauge medium
Grade 7
Measuring Circles
Content Standards 7.G.4 Know the formulas for the area and circumference of a circle and use them to solve problems; give an informal derivation of the relationship between the circumference and area of a circle.
Mathematical Practices MP.2 Reason abstractly and quantitatively. MP.4 Model with mathematics.

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