Problem 5. An observer is positioned 3km away from a rocket launch pad. How fast is the distance between the rocket and the observer increasing, when the rocket is 4km above the ground and is moving straight up at the speed of 300m/s?

Calculus: Early Transcendentals
8th Edition
ISBN:9781285741550
Author:James Stewart
Publisher:James Stewart
Chapter1: Functions And Models
Section: Chapter Questions
Problem 1RCC: (a) What is a function? What are its domain and range? (b) What is the graph of a function? (c) How...
icon
Related questions
Question
**Problem 5.** An observer is positioned \(3 \text{ km}\) away from a rocket launch pad. How fast is the distance between the rocket and the observer increasing, when the rocket is \(4 \text{ km}\) above the ground and is moving straight up at the speed of \(300 \text{ m/s}\)?

---

**Explanation:**

To solve this related rates problem, one needs to consider the position of the observer and the rocket as two vertices of a right triangle, with the horizontal distance from the observer to the launch pad forming one leg, the vertical distance from the launch pad to the rocket forming the other leg, and the hypotenuse representing the distance between the observer and the rocket.

Given:
1. Distance of observer from the launch pad: \(3 \text{ km}\)
2. Height of the rocket above the ground at the specific instance: \(4 \text{ km}\)
3. Vertical speed of the rocket: \(300 \text{ m/s}\) or \(0.3 \text{ km/s}\)

We need to find the rate at which the distance \(z\) between the observer and the rocket is increasing when the height \(y\) of the rocket is \(4 \text{ km}\).

---

**Steps Involving Pythagorean Theorem and Differentiation:**

1. Use the Pythagorean theorem to relate the distances:
   \[
   x^2 + y^2 = z^2
   \]
   where \(x = 3 \text{ km}\) (constant), \(y = 4 \text{ km}\), and \(z\) is the hypotenuse:
   \[
   3^2 + 4^2 = z^2 \implies 9 + 16 = 25 \implies z = 5 \text{ km}
   \]

2. Differentiate both sides of the Pythagorean theorem equation with respect to time \(t\):
   \[
   \frac{d}{dt} (x^2 + y^2 = z^2) \implies 2x \frac{dx}{dt} + 2y \frac{dy}{dt} = 2z \frac{dz}{dt}
   \]
   Since \(x\) is constant, \(\frac{dx}{dt} = 0\):
   \[
Transcribed Image Text:**Problem 5.** An observer is positioned \(3 \text{ km}\) away from a rocket launch pad. How fast is the distance between the rocket and the observer increasing, when the rocket is \(4 \text{ km}\) above the ground and is moving straight up at the speed of \(300 \text{ m/s}\)? --- **Explanation:** To solve this related rates problem, one needs to consider the position of the observer and the rocket as two vertices of a right triangle, with the horizontal distance from the observer to the launch pad forming one leg, the vertical distance from the launch pad to the rocket forming the other leg, and the hypotenuse representing the distance between the observer and the rocket. Given: 1. Distance of observer from the launch pad: \(3 \text{ km}\) 2. Height of the rocket above the ground at the specific instance: \(4 \text{ km}\) 3. Vertical speed of the rocket: \(300 \text{ m/s}\) or \(0.3 \text{ km/s}\) We need to find the rate at which the distance \(z\) between the observer and the rocket is increasing when the height \(y\) of the rocket is \(4 \text{ km}\). --- **Steps Involving Pythagorean Theorem and Differentiation:** 1. Use the Pythagorean theorem to relate the distances: \[ x^2 + y^2 = z^2 \] where \(x = 3 \text{ km}\) (constant), \(y = 4 \text{ km}\), and \(z\) is the hypotenuse: \[ 3^2 + 4^2 = z^2 \implies 9 + 16 = 25 \implies z = 5 \text{ km} \] 2. Differentiate both sides of the Pythagorean theorem equation with respect to time \(t\): \[ \frac{d}{dt} (x^2 + y^2 = z^2) \implies 2x \frac{dx}{dt} + 2y \frac{dy}{dt} = 2z \frac{dz}{dt} \] Since \(x\) is constant, \(\frac{dx}{dt} = 0\): \[
Expert Solution
steps

Step by step

Solved in 4 steps with 3 images

Blurred answer
Recommended textbooks for you
Calculus: Early Transcendentals
Calculus: Early Transcendentals
Calculus
ISBN:
9781285741550
Author:
James Stewart
Publisher:
Cengage Learning
Thomas' Calculus (14th Edition)
Thomas' Calculus (14th Edition)
Calculus
ISBN:
9780134438986
Author:
Joel R. Hass, Christopher E. Heil, Maurice D. Weir
Publisher:
PEARSON
Calculus: Early Transcendentals (3rd Edition)
Calculus: Early Transcendentals (3rd Edition)
Calculus
ISBN:
9780134763644
Author:
William L. Briggs, Lyle Cochran, Bernard Gillett, Eric Schulz
Publisher:
PEARSON
Calculus: Early Transcendentals
Calculus: Early Transcendentals
Calculus
ISBN:
9781319050740
Author:
Jon Rogawski, Colin Adams, Robert Franzosa
Publisher:
W. H. Freeman
Precalculus
Precalculus
Calculus
ISBN:
9780135189405
Author:
Michael Sullivan
Publisher:
PEARSON
Calculus: Early Transcendental Functions
Calculus: Early Transcendental Functions
Calculus
ISBN:
9781337552516
Author:
Ron Larson, Bruce H. Edwards
Publisher:
Cengage Learning