/*! 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} Problem 56 Your starship, the Aimless Wande... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Your starship, the Aimless Wanderer, lands on the mysterious planet Mongo. As chicf scientist-engineer, you make the following measurements: A \(2.50 \mathrm{~kg}\) stone thrown upward from the ground at \(12.0 \mathrm{~m} / \mathrm{s}\) returns to the ground in \(4.80 \mathrm{~s} ;\) the circumference of Mongo at the equator is \(2.00 \times 10^{5} \mathrm{~km} ;\) and there is no appreciable atmosphere on Mongo. The starship commander, Captain Confusion, asks for the following information: (a) What is the mass of Mongo? (b) If the Aimless Wanderer goes into a circular orbit \(30,000 \mathrm{~km}\) above the surface of Mongo. how many hours will it take the ship to complete one orbit?

Short Answer

Expert verified
The mass of Mongo is \(1.50 * 10^{24} kg\) and the Aimless Wanderer will take approximately 5.58 hours to complete one orbit.

Step by step solution

01

Calculate acceleration due to gravity

First, find the acceleration due to gravity on Mongo. This can be done using the equation for the motion of the stone: \(2 * g *t = v\) where \(v\) is the initial speed of the stone, and \(t\) is the total time. Solving for \(g\) gives \(g = v / (2 * t)\). Substituting the given values, \(g = 12.0 m/s / (2 * 4.80 s) = 1.25 m/s^2\).
02

Determine the mass of Mongo

Knowing the gravitational acceleration, find Mongo's mass using the equation for gravitational force, \(F = G * m * M / r^2\), where \(G\) is the universal gravitational constant, \(m\) is the mass of the stone, \(M\) is the mass of Mongo, and \(r\) is Mongo's radius. Since \(F = m * g\), we have \(m * g = G * m * M / r^2\). Cancel out \(m\) and solving the equation for \(M\) gives \(M = g * r^2 / G\). For the radius, we know the circumference is \(2 * \pi * r = 2.00 * 10^{5} km = 2.00 * 10^{8} m\), then \(r = 2.00 * 10^{8} m / (2 * \pi)\). Following substitution and calculation \(M = 1.25 m/s^2 * (2.00 * 10^{8} m / 2 * \pi) ^2 / 6.674 * 10^{-11} m^3 / kg / s^2 = 1.50 * 10^{24} kg\)
03

Calculate the time period of the orbit

For the Aimless Wanderer's circular orbit, use the equation for the period of a satellite in orbit around a planet, \(T = 2 * \pi * R / \sqrt{G * M / R}\), where \(R\) is the radius of the orbit. Given the Aimless Wanderer orbits \(30,000 km = 3.00 * 10^{7} m\) above the surface, the radius of the orbit is api surface radius plus orbit radius \(R = r + 3.00 * 10^{7} m\). Substituting and calculating \(T = 2 * \pi * (2.00 * 10^{8} m / 2 * \pi + 3.00 * 10^{7} m / 2 * \pi) / \sqrt{6.674 * 10^{-11} m^3 / kg / s^2 * 1.50 * 10^{24} kg / (2.00 * 10^{8} m / 2 * \pi + 3.00 * 10^{7} m / 2 * \pi)} = 2.01 * 10^{4} s\). To convert this into hours, divide by the number of seconds in an hour, \(3600 s/h\). So, the time period in hours is \(2.01 * 10^{4} s / 3600 s/h = 5.58 h\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Acceleration Due to Gravity
Understanding acceleration due to gravity is essential when analyzing the motion of objects near the surface of a planet. Gravity's acceleration, commonly symbolized as \( g \), is the rate at which an object speeds up as it falls freely. On Earth, this value is approximately \( 9.81 \text{ m/s}^2 \), but it varies on other planets. In the exercise, we needed to find the value of \( g \) on the planet Mongo. Given that a stone thrown upwards returns after a specific time (4.80 seconds) with an initial speed of \( 12.0 \text{ m/s} \), we can determine the acceleration due to gravity using the equation \( g = \frac{v}{2t} \). Substituting the numbers provided, Mongo's gravity ends up being \( 1.25 \text{ m/s}^2 \). This value is significantly lower than Earth's gravity, indicating a weaker gravitational pull on Mongo. This key finding helps us make further calculations, like the mass of Mongo.
Gravitational Force
Gravitational force is the attractive pull between any two masses. It plays a critical role in calculating orbits and understanding planetary dynamics. This force is described by Newton's law of universal gravitation, which states that the force between two objects is proportional to the product of their masses and inversely proportional to the square of the distance between them.The formula is \( F = G \frac{m_1 m_2}{r^2} \), where \( G = 6.674 \times 10^{-11} \text{ m}^3 \text{ kg}^{-1} \text{s}^{-2} \) is the universal gravitational constant. In the exercise, to find Mongo's mass \( M \), we used the derived formula from equating the gravitational force with the force due to Mongo's gravity on a stone. The resultant formula \( M = \frac{g r^2}{G} \) allows us to compute Mongo's mass once we know the planet's radius and acceleration due to gravity. Thus, by inputting these known quantities, we found Mongo's mass to be \( 1.50 \times 10^{24} \text{ kg} \). This calculated mass aids in understanding Mongo's gravitational pull and its implications for orbital mechanics.
Orbital Mechanics
Orbital mechanics is the study of the motions of bodies in space under the influence of gravitational forces. It's fundamental to understanding how spacecraft like the Aimless Wanderer operate around celestial objects. The orbital period, or the time it takes for a spacecraft to complete one orbit, is determined by the planet's gravitational characteristics and the orbit's radius. To calculate the orbital period \( T \), we use the formula \( T = 2\pi R / \sqrt{(G M / R)} \), where \( R \) is the sum of the planet's radius and the altitude of the orbit. In our task, we found the orbital period for the Aimless Wanderer orbiting 30,000 km (\( 3.00 \times 10^7 \text{ m} \)) above Mongo's surface. Adding this to the planet's radius gave us the total orbital radius. Following the substitution into the period formula, and converting seconds into hours, we determined that the ship would complete one orbit in approximately 5.58 hours. This short orbital period is due to the relatively small mass and gravitational pull of Mongo compared to larger celestial bodies like Earth.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Ten days after it was launched toward Mars in December 1998, the Mars Climate Orbiter spacecraft (mass 629 kg) was \(2.87 \times 10^{6} \mathrm{~km}\) from the earth and traveling at \(1.20 \times 10^{4} \mathrm{~km} / \mathrm{h}\) relative to the earth. At this time, what were (a) the spacecraft's kinetic energy relative to the earth and (b) the potential energy of the earthspacecraft system?

At the Galaxy's Core. Astronomers have observed a small, massive object at the center of our Milky Way galaxy (see Section 13.8). A ring of material orbits this massive object; the ring has a diameter of about 15 light-years and an orbital speed of about \(200 \mathrm{~km} / \mathrm{s}\) (a) Determine the mass of the object at the center of the Milky Way galaxy. Give your answer both in kilograms and in solar masses (one solar mass is the mass of the sun). (b) Observations of stars, as well as theories of the structure of stars, suggest that it is impossible for a single star to have a mass of more than about 50 solar masses. Can this massive object be a single, ordinary star? (c) Many astronomers believe that the massive object at the center of the Milky Way galaxy is a black hole. If so, what must the Schwarzschild radius of this black hole be? Would a black hole of this size fit inside the earth's orbit around the sun?

You are exploring a distant planet. When your spaceship is in a circular orbit at a distance of \(630 \mathrm{~km}\) above the planet's surface, the ship's orbital speed is \(4900 \mathrm{~m} / \mathrm{s}\). By observing the planet, you determine its radius to be \(4.48 \times 10^{6} \mathrm{~m}\). You then land on the surface and, at a place where the ground is level, launch a small projectile with initial speed \(12.6 \mathrm{~m} / \mathrm{s}\) at an angle of \(30.8^{\circ}\) above the horizontal. If resistance due to the planet's atmosphere is negligible, what is the horizontal range of the projectile?

Planet X rotates in the same manner as the earth, around an axis through its north and south poles, and is perfectly spherical. An astronaut who weighs \(943.0 \mathrm{~N}\) on the earth weighs \(915.0 \mathrm{~N}\) at the north pole of Planet \(X\) and only \(850.0 \mathrm{~N}\) at its equator. The distance from the north pole to the equator is \(18,850 \mathrm{~km}\), measured along the surface of Planet X. (a) How long is the day on Planet X? (b) If a \(45,000 \mathrm{~kg}\) satellite is placed in a circular orbit \(2000 \mathrm{~km}\) above the surface of Planet \(\mathrm{X}\). what will be its orbital period?

A rocket with mass \(5.00 \times 10^{3} \mathrm{~kg}\) is in a circular orbit of radius \(7.20 \times 10^{6} \mathrm{~m}\) around the earth. The rocket's engines fire for a period of time to increase that radius to \(8.80 \times 10^{6} \mathrm{~m},\) with the orbit again circular. (a) What is the change in the rocket's kinetic energy? Does the kinetic energy increase or decrease? (b) What is the change in the rocket's gravitational potential energy? Does the potential energy increase or decrease? (c) How much work is done by the rocket engines in changing the orbital radius?

See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.