Material & Energy Balances

Sidebar menu

 

Topic 2 Lesson 2
Units and dimensions, systems of units, dimensional homogeneity

 

Short answer questions

1. What is the value of gc in the SI system of units?

2. What is the value of gc in the American Engineering system of units?

3. If a force of 1 N is applied to an object with a mass of 1 kg, what is the resulting acceleration?

4. If a force of 1 lbf is applied to an object with a mass of 1 lbm, what is the resulting acceleration?

5. If a force of 1 lbf is applied to an object with a mass of 1 slug, what is the resulting acceleration?

6. An object has a weight of 1.0 lbf on Earth.

a. What is the mass of the object on Earth?
b. Would the object's mass be higher, lower or the same on the moon?
c. Would the object's weight be higher, lower or the same on the moon?

7. What is the value of the quantity g/gc in the SI system of units?

8. What is the value of the quantity g/gc in the AE system of units?

9. Did Newton formulate his second law before or after the English system of units was adopted?

10. g has a value of 32.174 ft/s2 on Earth. Is the value of g higher, lower or the same on Pluto?

11. gc has a value of 32.174 (lbm ft/s2)/lbf on Earth. Is the value of gc higher, lower or the same on Pluto?

12. What is the conversion factor to convert a temperature change in Fahrenheit to a temperature change in Celsius?

13. What is the expression to convert a temperature in Fahrenheit to a temperature in Celsius?

14. What is the conversion factor to convert a temperature in Rankine to a temperature in Kelvin?

15. What is the expression to convert a temperature in Kelvin to a temperature in Celsius?

16. What temperature corresponds to a complete lack of thermal motion?

17. Is the following equation dimensionally homogeneous? (The symbols have the same meaning as in the lecture) P = Po + gh/gc

18. True or false, an equation could be valid if it is not dimensionally homogeneous?

19. True or false, an equation must be valid if it is dimensionally homogeneous?

20. True or false, if an equation is valid it must be dimensionally homogeneous?

Go previous page arrow

Page 14 of 15

Go next page arrow

Go to:    


E-mail icon

E-mail comments and questions to your instructor!


© Copyright University of Iowa 2003