Chapter 2: Problem 5
\(y^{\prime}+t y^{1 / 3}=\tan t, \quad y(-1)=1\)
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none}
Learning Materials
Features
Discover
Chapter 2: Problem 5
\(y^{\prime}+t y^{1 / 3}=\tan t, \quad y(-1)=1\)
These are the key concepts you need to understand to accurately answer the question.
All the tools & learning materials you need for study success - in one app.
Get started for free
Let \(S(t)\) represent the amount of a chemical reactant present at time \(t, t \geq 0\). Assume that \(S(t)\) can be determined by solving the initial value problem $$ S^{\prime}=-\frac{\alpha S}{K+S}, \quad S(0)=S_{0}, $$ where \(\alpha, K\), and \(S_{0}\) are positive constants. Obtain an implicit solution of the initial value problem. (The differential equation, often referred to as the Michaelis-Menten equation, arises in the study of biochemical reactions.)
The motion of a body of mass \(m\), gravitationally attracted to Earth in the presence of a resisting drag force proportional to the square of its velocity, is given by $$ m \frac{d v}{d t}=-\frac{G m M_{e}}{r^{2}}+\kappa v^{2} $$ [recall equation (13)]. In this equation, \(r\) is the radial distance of the body from the center of Earth, \(G\) is the universal gravitational constant, \(M_{e}\) is the mass of Earth, and \(v=d r / d t\). Note that the drag force is positive, since it acts in the positive \(r\) direction. (a) Assume that the body is released from rest at an altitude \(h\) above the surface of Earth. Recast the differential equation so that distance \(r\) is the independent variable. State an appropriate initial condition for the new problem. (b) Show that the impact velocity can be expressed as $$ v_{\text {impact }}=-\left[2 G M_{e} \int_{0}^{h} \frac{e^{-2(\kappa / m) s}}{\left(R_{e}+s\right)^{2}} d s\right]^{1 / 2}, $$ where \(R_{e}\) represents the radius of Earth. (The minus sign reflects the fact that \(v=d r / d t<0 .)\)
Assume Newton's law of cooling applies. An object, initially at \(150^{\circ} \mathrm{F}\), was placed in a constant- temperature bath. After 2 \(\min\), the temperature of the object had dropped to \(100^{\circ} \mathrm{F}\); after \(4 \mathrm{~min}\), the object's temperature was observed to be \(90^{\circ} \mathrm{F}\). What is the temperature of the bath?
Use the ideas of Exercise 32 to solve the given initial value problem. Obtain an explicit solution if possible. $$ y^{\prime}=(t+y)^{2}-1, \quad y(1)=2 $$
Consider the following autonomous first order differential equations: $$ y^{\prime}=-y^{2}, \quad y^{\prime}=y^{3}, \quad y^{\prime}=y(4-y) . $$ Match each of these equations with one of the solution graphs shown. Note that each solution satisfies the initial condition \(y(0)=1\). Can you match them without solving the differential equations?
What do you think about this solution?
We value your feedback to improve our textbook solutions.