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Ch 06: Dynamics I: Motion Along a Line
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796당신이 사용하는 게 아니라요?교과서 변경
6장, 문제 13b

A 50 kg box hangs from a rope. What is the tension in the rope if: The box moves up at a steady 5.0 m/s?

검증된 단계별 안내
1
Identify the forces acting on the box: The box is subject to two forces: the gravitational force (weight) acting downward and the tension in the rope acting upward.
Understand the condition of motion: Since the box is moving upward at a steady speed of 5.0 m/s, it is in dynamic equilibrium. This means the net force acting on the box is zero because there is no acceleration.
Express the forces mathematically: The gravitational force is given by \( F_g = m \cdot g \), where \( m \) is the mass of the box (50 kg) and \( g \) is the acceleration due to gravity (approximately 9.8 m/s²). The tension in the rope, \( T \), must balance this force to maintain constant velocity.
Set up the equation for equilibrium: Since the net force is zero, \( T - F_g = 0 \). Rearrange this to find \( T = F_g \).
Substitute the values into the equation: Replace \( m \) with 50 kg and \( g \) with 9.8 m/s² in the equation \( T = m \cdot g \) to calculate the tension in the rope.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m

주요 개념

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

Tension in a Rope

Tension is the force transmitted through a rope or string when it is pulled tight by forces acting from opposite ends. In this scenario, the tension in the rope must counteract the weight of the box and provide the necessary force to maintain its steady upward motion.
추천 영상:
가이드 코스
06:34
Calculating Tension in a Pendulum with Energy Conservation

Newton's Second Law of Motion

Newton's Second Law states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. In this case, since the box moves at a constant velocity (steady 5.0 m/s), the net force is zero, indicating that the upward tension equals the downward gravitational force.
추천 영상:
가이드 코스
06:54
Intro to Forces & Newton's Second Law

Weight of an Object

The weight of an object is the force exerted on it due to gravity, calculated as the product of its mass and the acceleration due to gravity (approximately 9.81 m/s² on Earth). For the 50 kg box, the weight is 50 kg × 9.81 m/s², which is essential for determining the tension in the rope when the box is in motion.
추천 영상:
가이드 코스
10:19
Torque Due to Weight