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Ch 10: Interactions and Potential Energy
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796당신이 사용하는 게 아니라요?교과서 변경
10장, 문제 17

A stretched spring stores 2.0 J of energy. How much energy will be stored if the spring is stretched three times as far?

검증된 단계별 안내
1
Understand that the energy stored in a spring is given by the formula: Es = 12kx2, where k is the spring constant and x is the displacement from the equilibrium position.
Recognize that the energy stored in the spring is proportional to the square of the displacement, as indicated by the x2 term in the formula.
If the spring is stretched three times as far, the new displacement becomes x' = 3x. Substitute this into the energy formula: Es' = 12k(3x)2.
Simplify the expression for the new energy: Es' = 12k(9x2) = 912kx2.
Compare the new energy to the original energy. Since the original energy is Es = 12kx2, the new energy is 9 times the original energy. Multiply the original energy (2.0 J) by 9 to find the new energy.

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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Hooke's Law

Hooke's Law states that the force exerted by a spring is directly proportional to the distance it is stretched or compressed from its equilibrium position, represented mathematically as F = kx, where F is the force, k is the spring constant, and x is the displacement. This principle is fundamental in understanding how springs behave under different loads.
추천 영상:
가이드 코스
05:27
Spring Force (Hooke's Law)

Elastic Potential Energy

Elastic potential energy is the energy stored in a spring when it is stretched or compressed. The formula for elastic potential energy (U) is U = 1/2 kx², where k is the spring constant and x is the displacement from the equilibrium position. This concept is crucial for calculating the energy stored in a spring based on its deformation.
추천 영상:
가이드 코스
07:24
Potential Energy Graphs

Energy Scaling with Displacement

The energy stored in a spring scales with the square of the displacement. This means that if the displacement is tripled, the energy stored increases by a factor of nine (since (3x)² = 9x²). Understanding this relationship is essential for predicting how much energy will be stored when the spring is stretched to different lengths.
추천 영상:
가이드 코스
06:13
Displacement vs. Distance
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