Ch. 02 - Describing Motion: Kinematics in One Dimension

Giancoli Douglas - Physics for Scientists and Engineers 5th edition

Giancoli Douglas5th editionPhysics for Scientists and EngineersISBN: 9780137488179Not the one you use?Change textbook

Giancoli Douglas 5th edition

Ch. 02 - Describing Motion: Kinematics in One Dimension

Problem 30b

Chapter 2, Problem 30b

Figure 2–42 shows the velocity of a train as a function of time. During what periods, if any, was the velocity constant?

Verified step by step guidance

Examine the velocity vs. time graph provided in the problem. A constant velocity corresponds to a horizontal line on the graph, where the slope of the line is zero.

Identify the time intervals on the graph where the slope of the velocity curve is zero. These intervals represent periods during which the velocity does not change with time.

Note that during these intervals, the train is neither accelerating nor decelerating, as the acceleration (rate of change of velocity) is zero.

Mark the specific time periods (e.g., t1 to t2) on the graph where the velocity remains constant. These are the flat, horizontal segments of the graph.

Summarize the identified time intervals as the periods during which the velocity of the train was constant, based on the graph's visual representation.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Velocity

Velocity is a vector quantity that refers to the rate at which an object changes its position. It is defined as the displacement of the object divided by the time taken for that displacement. In the context of the question, understanding velocity is crucial to determine when it remains constant, which is indicated by a horizontal line on a velocity vs. time graph.

Constant Velocity

Constant velocity occurs when an object moves at a uniform speed in a straight line, meaning there is no change in speed or direction over time. On a velocity vs. time graph, this is represented by a flat, horizontal line. Identifying periods of constant velocity in the graph is essential for answering the question accurately.

Graph Interpretation

Graph interpretation involves analyzing graphical data to extract meaningful information. In this case, it requires understanding how to read a velocity vs. time graph to identify sections where the velocity remains unchanged. This skill is vital for determining the specific time intervals during which the train's velocity is constant.

Recommended video:

Guided course

07:32

Graphing Position, Velocity, and Acceleration Graphs

Related Practice

Textbook Question

Figure 2–42 shows the velocity of a train as a function of time. At what time was its velocity greatest?

views

Textbook Question

A baseball pitcher throws a baseball with a speed of 43 m/s. Estimate the average acceleration of the ball during the throwing motion. In throwing the baseball, the pitcher accelerates it through a displacement of about 3.5 m, from behind the body to the point where it is released (Fig. 2–44).

<IMAGE>

views

Textbook Question

The position of an object is given by 𝓍 = At + Bt², where 𝓍 is in meters and t is in seconds. What are the units of A and B?

views

Textbook Question

A car traveling 85 km/h slows down at a constant 0.50 m/s² just by 'letting up on the gas.' Calculate the distance it travels during the first and fifth seconds.

views

Textbook Question

A bowling ball traveling with constant speed hits the pins at the end of a bowling lane 16.5 m long. The bowler hears the sound of the ball hitting the pins 2.75 s after the ball is released from his hands. What is the speed of the ball, assuming the speed of sound is 340 m/s?

views

Textbook Question

Figure 2–42 shows the velocity of a train as a function of time. During what periods, if any, was the acceleration constant?

views