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Ch 03: Motion in Two or Three Dimensions
Young & Freedman Calc - University Physics 14th Edition
Young & Freedman Calc14th EditionUniversity PhysicsISBN: 9780321973610당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 6a

A dog running in an open field has components of velocity vx = 2.6 m/s and vy = −1.8 m/s at t1 = 10.0 s. For the time interval from t1 = 10.0 s to t2 = 20.0 s, the average acceleration of the dog has magnitude 0.45 m/s2 and direction 31.0° measured from the +x–axis toward the +y–axis. At t2 = 20.0 s, what are the x- and y-components of the dog's velocity?

검증된 단계별 안내
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Start by understanding the given information: the initial velocity components at t1 = 10.0 s are υx = 2.6 m/s and υy = −1.8 m/s. The average acceleration over the time interval from t1 to t2 is 0.45 m/s² at an angle of 31.0° from the +x-axis toward the +y-axis.
Break down the average acceleration into its x and y components using trigonometry. The x-component of acceleration (ax) can be found using ax = a * cos(θ), and the y-component (ay) using ay = a * sin(θ), where a = 0.45 m/s² and θ = 31.0°.
Calculate the change in velocity for each component using the formula Δυ = a * Δt, where Δt = t2 - t1 = 20.0 s - 10.0 s = 10.0 s. Apply this formula separately for the x and y components using the respective acceleration components calculated in the previous step.
Determine the final velocity components at t2 = 20.0 s by adding the change in velocity to the initial velocity components. For the x-component, use υx_final = υx_initial + Δυx, and for the y-component, use υy_final = υy_initial + Δυy.
Summarize the process: You have calculated the x and y components of the dog's velocity at t2 by considering the initial velocity, the average acceleration, and the time interval. This approach allows you to find the final velocity components without directly calculating the numerical values.

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주요 개념

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

Velocity Components

Velocity components refer to the projection of velocity along the coordinate axes, typically x and y. In this problem, the dog's velocity is given in terms of its x-component (υx = 2.6 m/s) and y-component (υy = −1.8 m/s). Understanding these components is crucial for calculating changes in velocity due to acceleration over time.
추천 영상:
가이드 코스
05:53
Calculating Velocity Components

Average Acceleration

Average acceleration is the change in velocity over a given time interval, expressed as a vector with both magnitude and direction. Here, the average acceleration is 0.45 m/s² at an angle of 31.0° from the +x-axis toward the +y-axis. This concept helps determine how the velocity components change from t1 to t2.
추천 영상:
가이드 코스
05:44
Solving Constant and Average Velocity Problems

Vector Addition

Vector addition involves combining vectors to find resultant vectors, such as velocity or acceleration. In this context, it is used to calculate the new velocity components at t2 by adding the initial velocity components to the change in velocity due to acceleration, considering both magnitude and direction.
추천 영상:
가이드 코스
07:30
Vector Addition By Components
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