Lecture_09042009_Compatibility_Mode_

# Lecture_09042009_Compatibility_Mode_ - ENGR 301 ENGR 301...

This preview shows pages 1–13. Sign up to view the full content.

ENGR 301 Thermodynamics 9/04/2009 Madison 201 MW 12:00 – 1:15 PM ENGR 301

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
WORK and HEAT Energy in transit Path functions - Associated with process, not the states - Do not have exact differentials Q ? Question: Are work and heat system properties? Can you assign work and heat to system characteristics? Can we define work and heat per unit mass of system? ENGR 301
ENGR 301

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Electric WORK Electric POWER W = V N (J) W = V I (J/s or W) e V N e V I = V I Δ t ENGR 301
ENGR 301

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Work for raising a body = change in potential energy = m g Δ Z Work for accelerating a body = change in KE = (m/2) (v 2 2 – v 1 2 ) ENGR 301
Car is at rest at the bottom of slope. It is accelerated so that it achieves a speed of 90 km/h in 12.5 seconds. How much power is needed in order to achieve this acceleration? V 1 = 0 m/s V 2 = 90 km/h = 25 m/s 1 0 m/s, V 90 km/h 25 m/s Δ t = 12.5 s Æ acceleration = 2 m/s 2 Distance traveled = 156.25 m Gain in elevation = 78.125 m Work done in acceleration = (m/2) (v 2 2 -v 1 2 ) = 375,000 J or 375 kJ Work done in elevation = m g Δ Z = 919,687.5 J or 919.6785 kJ Net work done = 1294.7 kJ Power needed

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern