• Study Resource
  • Explore
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Mechanics Practice Problem Set
Mechanics Practice Problem Set

Impact Mechanics - Assets - Cambridge University Press
Impact Mechanics - Assets - Cambridge University Press

PHY101 - National Open University of Nigeria
PHY101 - National Open University of Nigeria

Lightning Protection of Buildings Using Active Finials
Lightning Protection of Buildings Using Active Finials

Physics – 1st Quarter
Physics – 1st Quarter

Explanation - Physicsland
Explanation - Physicsland

Two Interpretations of Rigidity in Rigid Body Collisions
Two Interpretations of Rigidity in Rigid Body Collisions

... time, the relative displacement between pairs of points that are not in the contact-deformation regions (say points R and P) can be accurately calculated by treating the spheres as rigid everywhere except in a small, localized contact region governed by the Hertz relations. In general point-contact ...
Oscillatory Motion and Mechanical Waves Oscillatory Motion and
Oscillatory Motion and Mechanical Waves Oscillatory Motion and

Chapter 6 Momentum Analysis of Flow Systems
Chapter 6 Momentum Analysis of Flow Systems

... nearly uniform and thus the effect of the momentum-flux correction factor is negligible, β ≅ 1. Analysis We take the plate as the control volume. The relative velocity between the plate and the jet is V when the plate is stationary, and 1.5V when the plate is moving with a velocity ½V towards the pl ...
Chapter 9 Rotational Motion
Chapter 9 Rotational Motion

Chapter 7 LINEAR MOMENTUM
Chapter 7 LINEAR MOMENTUM

... propelling it forward. Similarly, a rocket engine expels exhaust from burning fuel to propel itself forward. 9. First law: The momentum of an object is constant unless acted upon by an external force. Second law: The net force acting on an object is equal to the rate of change of the object’s moment ...
8 Momentum - mrfosterscience
8 Momentum - mrfosterscience

Chapter 7: Linear Momentum and Collisions
Chapter 7: Linear Momentum and Collisions

to the file
to the file

... gravity is broken down into components, one acting perpendicular to the inclined ramp and one acting parallel to the inclined ramp. The component of the force of gravity that is parallel to the inclined ramp causes the object (vehicle in this case) to move down the ramp, if that component is greater ...
paper pattern - Target Publications
paper pattern - Target Publications

Study of the Effect of AC Electric Potential Applied on Co
Study of the Effect of AC Electric Potential Applied on Co

Low-Melting-Temperature Metals for Possible
Low-Melting-Temperature Metals for Possible

Mass spectrometry - ERTE
Mass spectrometry - ERTE

Conservation of Momentum
Conservation of Momentum

Explaining the subpulse drift velocity of pulsar
Explaining the subpulse drift velocity of pulsar

Kinetics of a Particle
Kinetics of a Particle

Problem 15.1 In Active Example 15.1, what is the velocity of the
Problem 15.1 In Active Example 15.1, what is the velocity of the

Std. 12 Physics, MCQs
Std. 12 Physics, MCQs

Phys114 -2013 Sample Problems ____ 1. A bullet is fired through a
Phys114 -2013 Sample Problems ____ 1. A bullet is fired through a

Document
Document

... Any other use of the materials is governed by the general copyright statement that follows. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, without written permission from the publisher. Heriot-Watt Universi ...
< 1 2 3 4 5 6 7 ... 156 >

Specific impulse

Specific impulse (usually abbreviated Isp) is a measure of the efficiency of rocket and jet engines. By definition, it is the impulse delivered per unit of propellant consumed, and is dimensionally equivalent to the thrust generated per unit propellant flow rate. If mass (kilogram or slug) is used as the unit of propellant, then specific impulse has units of velocity. If weight (newton or pound) is used instead, then specific impulse has units of time (seconds). The conversion constant between these two versions is the standard gravitational acceleration constant (g0). The higher the specific impulse, the lower the propellant flow rate required for a given thrust, and in the case of a rocket, the less propellant needed for a given delta-v, per the Tsiolkovsky rocket equation.Specific impulse is a useful value to compare engines, much like miles per gallon or liters per 100 kilometers is used for cars. A propulsion method and system with a higher specific impulse is more propellant-efficient. While the unit of seconds can seem confusing to laypeople, it is fairly simple to understand as ""hover-time"": how long a rocket can ""hover"" before running out of fuel, given the weight of that propellant/fuel. Of course, the weight of the rocket has to be taken out of consideration and so does the reduction in fuel weight as it's expended; the basic idea is ""how long can any given amount of x hold itself up"". Obviously that must mean ""...against Earth's gravity"", which means nothing in non-Earth conditions; hence Isp being given in velocity when propellant is measured in mass rather than weight, and the question becomes ""how fast can any given amount of x accelerate itself?""Note that Isp describes efficiency in terms of amount of propellant, and does not include the engine, structure or power source. Higher Isp means less propellant needed to impart a given momentum. Some systems with very high Isp (cf. ion thrusters) may have relatively very heavy/massive power generators, and produce thrust over a long period; thus, while they are ""efficient"" in terms of propellant mass carried, they may actually be quite poor at delivering high thrust as compared to ""less efficient"" engine/propellant designs.Another number that measures the same thing, usually used for air breathing jet engines, is specific fuel consumption. Specific fuel consumption is inversely proportional to specific impulse and the effective exhaust velocity. The actual exhaust velocity is the average speed of the exhaust jet, which includes fuel combustion products, nitrogen, and argon, as it leaves air breathing engine. The effective exhaust velocity is the exhaust velocity that the combusted fuel and atmospheric oxygen only would need to produce the same thrust. The two are identical for an ideal rocket working in vacuum, but are radically different for an air-breathing jet engine that obtains extra thrust by accelerating the non-combustible components of the air. Specific impulse and effective exhaust velocity are proportional.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report