Problem 3: 25 points

Cell culture media is, flowing through a cylindrical tube at a volumetric flow rate of 12 ml/s. The tube has a diameter of 0.8 cm and length of 12 cm. Assume the viscosity of the media is 1.2 cP (0.0012 Pa s).

 

    A. What is the shear rate at the wall of the tube? (5 points)

 

    B. What is the shear rate at the centerline of the tube? ( 5 points)

 

    C. What is the shear stress at the wall of the tube? ( 5 points)

TAMU ECCB/RENR 205 where can we find the answers to the clicker questions. The professor never answers them..

Check answers: Question 1 (1 point)   Saved      

Bacteria numbers can triple in 20 minutes.

  Question 1 options: True False  

Question 2 (1 point)   Saved            

When removing a pot lid, tilt the cover away from you.

  Question 2 options: True False  

Question 3 (1 point)   Saved            

Most cases of Food Borne Illness are preventable.

  Question 3 options: True False  

Question 4 (1 point)   Saved            

Class A fire extinguishers are used for ordinary combustibles like paper, wood and cloth.

  Question 4 options: True False  

Question 5 (1 point)   Saved            

Allow knives to soak in soapy dishwater to ensure they are cleaned thoroughly.

  Question 5 options: True False  

Question 6 (1 point)   Saved            

Hands need only be washed at the beginning and end of all food labs.

  Question 6 options: True False  

Question 7 (1 point)   Saved            

The safest way to carry a knife is by having the blade pointed in front of you.

  Question 7 options: True False  

Question 8 (1 point)   Saved            

If you drop a knife, you should try to catch it before it hits your foot.

  Question 8 options: True False  

Question 9 (1 point)   Saved            

If you have a burn, you should submerge it into ice cold water until the pain stops.

  Question 9 options: True False  

Question 10 (1 point)   Saved            

When in a hurry, it is okay to defrost food on the kitchen counter.

  Question 10 options: True False  

Please answer the 4 questions correctly.

1. Applying Concepts

All mammals have the same size hearts relative to their body size. Do their hearts beat at the same rate?

2. Interpreting Data

a. What is the resting pulse rate of a 7,000-kilogram African bull elephant?

b. What is the resting pulse rate of a 20-gram mouse? How many complete heartbeats is that per second?

c. What general statement can be made regarding the effect of body size on heart rate in mammals?

3. Making Inferences

a. The data in the graph, plotted on logarithmic coordinates (that is, the scale rises in powers of 10) fall nicely upon a straight line. How would you expect them to look plotted on their linear coordinates?

b. As you walk through the graph from left to right, the line slopes down. This is called a negative slope. What does the negative slope of the line signify?

4. Drawing Conclusions

If you plotted data for an experiment measuring body mass versus resting oxygen consumption, you would get exactly the same slope of the line as shown in this graph. What does this tell us about why body size affects heart rate in mammals as is does?