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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 60a

A 100 g particle experiences the one-dimensional, conservative force Fx shown in FIGURE P10.60. Let the zero of potential energy be at x = 0 m . What is the potential energy at x = 1.0, 2.0, 3.0, and 4.0 m? Hint: Use the definition of potential energy and the geometric interpretation of work.

검증된 단계별 안내
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Step 1: Recall the relationship between force and potential energy in one dimension: \( U(x) = - \int F_x \, dx \). The potential energy at a given position is determined by integrating the force over the distance from the reference point (where \( U(0) = 0 \)).
Step 2: Analyze the graph of \( F_x \). From \( x = 0 \) to \( x = 4 \), the force is constant at \( F_x = 10 \; \text{N} \). The work done (and thus the change in potential energy) is the area under the curve, which is a rectangle with height \( 10 \; \text{N} \) and width \( x \).
Step 3: From \( x = 4 \) to \( x = 8 \), the force decreases linearly from \( 10 \; \text{N} \) to \( 0 \; \text{N} \). The work done is the area of a triangle with base \( 4 \; \text{m} \) and height \( 10 \; \text{N} \). Use the formula for the area of a triangle: \( \text{Area} = \frac{1}{2} \times \text{base} \times \text{height} \).
Step 4: From \( x = 8 \) to \( x = 10 \), the force is zero, so no additional work is done, and the potential energy remains constant beyond \( x = 8 \).
Step 5: Calculate the potential energy at \( x = 1.0 \; \text{m}, \; x = 2.0 \; \text{m}, \; x = 3.0 \; \text{m}, \; \text{and} \; x = 4.0 \; \text{m} \) by summing the areas under the curve up to each position. For \( x > 4 \), include the triangular area contribution from \( x = 4 \) to \( x = 8 \).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
8m
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주요 개념

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

Conservative Forces

A conservative force is one where the work done by the force on an object moving between two points is independent of the path taken. This means that the work done can be fully recovered as potential energy. In this problem, the force Fx is conservative, allowing us to relate the force to potential energy through the work-energy principle.
추천 영상:
가이드 코스
06:43
Energy Conservation with Non-Conservative Forces

Potential Energy (U)

Potential energy is the energy stored in an object due to its position in a force field, such as gravitational or elastic fields. For conservative forces, potential energy can be calculated by integrating the force over a distance. In this case, we will calculate the potential energy at various positions by considering the area under the force versus position graph.
추천 영상:
가이드 코스
06:35
Gravitational Potential Energy

Work-Energy Theorem

The work-energy theorem states that the work done on an object is equal to the change in its kinetic energy. For conservative forces, the work done can also be expressed as the negative change in potential energy. This relationship allows us to find potential energy values at different positions by calculating the work done by the force as the particle moves from the reference point.
추천 영상:
가이드 코스
04:10
The Work-Energy Theorem
관련 실천
교과서 질문

A 1.0 kg mass that can move along the x-axis experiences the potential energy U = (x²−x) J, where x is in m. The mass has velocity vx = 3.0 m/s at position x = 1.0 m. At what position has it slowed to 1.0 m/s?

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교과서 질문

A system has potential energy U(x)=(10J)[1sin((3.14rad/m)x)]U(x) = (10 \, \(\text{J}\)) [1 - \(\sin\)((3.14 \, \(\text{rad/m}\)) x)] as a particle moves over the range 0 m x3 m0\(\text{ m }\]\le\) x\(\le\)3\(\text{ m}\). For each, is it a point of stable or unstable equilibrium?

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교과서 질문

A particle that can move along the x-axis is part of a system with potential energy U(x) = A/x2 − B/x where A and B are positive constants. Where are the particle's equilibrium positions?

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교과서 질문

CALC A 2.6 kg block is attached to a horizontal rope that exerts a variable force Fx = (20 − 5x) N, where x is in m. The coefficient of kinetic friction between the block and the floor is 0.25. Initially the block is at rest at x = 0 m. What is the block's speed when it has been pulled to x = 4.0 m?

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교과서 질문

A 100 g particle experiences the one-dimensional, conservative force Fx shown in FIGURE P10.60. Suppose the particle is shot to the right from x = 1.0 m with a speed of 25 m/s. Where is its turning point?

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교과서 질문

A clever engineer designs a 'sprong' that obeys the force law Fx=−q(x−xeq)³ , where xeq is the equilibrium position of the end of the sprong and q is the sprong constant. For simplicity, we'll let xeq = 0 m .Then Fx = −qx³. Find an expression for the potential energy of a stretched or compressed sprong.

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