Essential University Physics
4th Edition
ISBN: 9780134988559
Author: Wolfson, Richard
Publisher: Pearson Education,
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Textbook Question
Chapter 4, Problem 48P
Find expressions for the force needed to bring an object of mass m from rest to speed v (a) in lime Δt and (b) over distance Δx.
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A person with mass m is skateboarding across level ground on earth with a speed vo when they
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i
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d →
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A mass m is suspended from a massless spring
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For t < 0, an object of mass m experiences no force and moves in the positive x direction with a constant speed vi. Beginning at t = 0, when the object passes position x = 0, it experiences a net resistive force proportional to the square of its speed: net = −mkv2î, where k is a constant. The speed of the object after t = 0 is given by
v = vi/(1 + kvit).
(a) Find the position x of the object as a function of time. (Use the following as necessary: k, m, t, and vi.)x(t) =
(b) Find the object's velocity as a function of position. (Use the following as necessary: k, m, t, vi, and x.)
v(t)=
Chapter 4 Solutions
Essential University Physics
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