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Skills WorksheetCONNECTION TO FINE ARTS
Cross-Disciplinary
The Motions of Dance
Read the following paragraphs, and complete the exercises below.
A dancer can leap through the air like a gazelle, seemingly defying gravity. Then, the dancer may spin like a top and laterstand totally still on the tip of a single toe. In each case, the dancer is obeying—or taking advantage of—the laws of physics.
BALANCE
Whether in motion or at rest, dancers are experts at maintaining their balance. A number of physical principles influence the balance of a dancer. One principle is Newton’s first law of motion: An object maintains its state of motion or rest unless it experiences an unbalanced force. For the ballerina to remain balanced, the sum of the forces acting on the ballerina must be zero. For the dancer to remain still on her toes, the force of gravity—the dancer’s weight—must be equaled by an upward force exerted on the dancer by the floor.
CENTER OF GRAVITY
In addition, the dancer’s center of gravity must be at a point on a vertical line passing through the dancer’s body and through the tip of her toe at the floor. At that point, forces pushing the dancer in various directions cancel one another. The added force of a step, leap, or spin will set the dancer in motion again.
Exercises
1.According to Newton’s first law, what will happen to an object that experiences an unbalanced force?
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2.How is the motion of a dancer related to the balance of forces acting on the dancer’s body?
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3.Why is it easier to stand on a flat foot than on a single toe? Explain your reasoning.
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Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
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