Concept explainers
A particle’s velocity is given by
- a. Describe the particle’s motion. In particular, is it speeding up, slowing down, or maintaining constant speed?
- b. Find the particle’s velocity at t = 0, t = 10.0 s, and t = 5.00 min.
- c. Find the particle’s speed at t = 0, t = 10.0 s, and t = 5.00 min.
(a)
The motion of the particle.
Answer to Problem 31PQ
The particle is speeding up.
Explanation of Solution
When the particle is moving, as time increases, the velocity of the particle increases. As velocity increases with time, the motion of the particle can be described as increasing speed.
Therefore, the particle is speeding up.
(b)
The particle’s velocity at
Answer to Problem 31PQ
The particle’s velocity at
Explanation of Solution
Write the expression for the value of the velocity of the particle in terms of the time taken.
Here,
Conclusion:
Substitute
Substitute
Substitute
Therefore, the particle’s velocity at
(c)
The particle’s speed at
Answer to Problem 31PQ
The particle’s speed at
Explanation of Solution
Write the expression for the value of the speed of the particle in terms of the time taken.
Here,
Conclusion:
Substitute
Substitute
Substitute
Therefore, the particle’s velocity at
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Chapter 2 Solutions
Student Solutions Manual For Katz's Physics For Scientists And Engineers: Foundations And Connections, Volume 1
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