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Ch 02: Motion Along a Straight Line
Young & Freedman Calc - University Physics 14th Edition
Young & Freedman Calc14th EditionUniversity PhysicsISBN: 9780321973610당신이 사용하는 게 아니라요?교과서 변경
2장, 문제 10c

A physics professor leaves her house and walks along the sidewalk toward campus. After 55 min, it starts to rain, and she returns home. Her distance from her house as a function of time is shown in Fig. E2.102.10. At which of the labeled points is her velocity constant and negative?
Position-time graph showing a curve with labeled points I to V; velocity is zero at point IV.

검증된 단계별 안내
1
To determine where the velocity is constant and negative, we need to analyze the slope of the distance-time graph. A constant velocity corresponds to a straight line segment on the graph.
A negative velocity indicates that the slope of the line is negative, meaning the line is sloping downwards as time progresses.
Examine the graph and identify the segments where the line is straight and sloping downwards. This will indicate a constant negative velocity.
From the graph, observe the segment between points 'c' and 'b'. This segment is a straight line with a negative slope, indicating a constant negative velocity.
Therefore, the velocity is constant and negative between points 'c' and 'b'.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m
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주요 개념

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

Velocity

Velocity is a vector quantity that describes the rate of change of position with respect to time, including both speed and direction. In the context of the graph, velocity is represented by the slope of the line. A constant negative velocity indicates a straight line with a downward slope, showing movement in the opposite direction.
추천 영상:
가이드 코스
7:27
Escape Velocity

Position-Time Graph

A position-time graph displays an object's position relative to time, allowing analysis of motion characteristics such as velocity and acceleration. The slope of the graph at any point indicates the object's velocity. A negative slope signifies movement back toward the starting point, while a constant slope indicates uniform motion.
추천 영상:
가이드 코스
03:04
Curved Position-Time Graphs & Acceleration

Slope of a Line

The slope of a line on a graph represents the rate of change between the variables on the axes. In a position-time graph, the slope corresponds to velocity. A negative slope indicates a decrease in position over time, meaning the object is moving back toward its starting point. A constant slope implies uniform velocity.
추천 영상:
가이드 코스
01:29
Slopes of Lines
관련 실천
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A physics professor leaves her house and walks along the sidewalk toward campus. After 55 min, it starts to rain, and she returns home. Her distance from her house as a function of time is shown in Fig. E2.102.10. At which of the labeled points is her velocity constant and positive?

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교과서 질문

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