Spring, 2012 Homework Set 1
Only Problems in Bold are Submitted for Grading
Set 1.1 -
Complete for quiz on Feb. 7 Turn in bolded (statistics and additional 1-3) problems by Feb. 7 and prepare for Quiz on Feb. 12
Statistics Calculations Problems (See Chem. 133 Lab Manual pages 3-4)
Solutions to Statistics Problems
From Rubinson and Rubinson: 6.1, 6.2, 6.3, 6.5, 6.6, 6.7
Solutions to Rubinson and Rubinson problems
Solution to Additional Problems to be turned in
Solution to last Additional Problem
Homework Set 1.2:
Complete for quiz on Feb. 21 Turn in additional problem 3 by Feb. 21 and prepare for Quiz on Feb. 26
From Rubinson and Rubinson: 6.19
Solution to Problems not to be turned in (R&R 6.19 + problems 1, 2 and 4)
Solution to turned in Problem
Homework Set 1.3: Complete by March 5 (but no quiz planned)
From Rubinson and Rubinson: 6.13, 6.15
1. Which type of noise is best reduced by shielding the critical electronics?
2. An instrument measures the concentration of a compound in a river that varies on the order of minutes. Most of the noise associated with the measurement occurs at frequencies greater than 1 Hz. Suggest a method (analog or digital) to increase the signal to noise ratio.
3. What type of noise can be reduced by using internal amplification in a transducer?
4. What type of noise can be reduced by cooling electrical components?
5. A sample is measured 12 times by a spectroscopic method. The average concentration and standard deviation in the average are found to be 5.2+0.7 μM. With the assumptions made below answer the following questions:
Assume: 1) noise is purely random, 2) the noise is defined as the standard deviation, and 3) that the standard deviation is well-represented. (The third assumption allows you to avoid using t-factors in signal averaging)
a) What signal to noise ratio would be expected in a single measurement?
b) What is the signal to noise in the average value for the twelve measurements?
c) A researcher needs to have the noise be less than 2% of the value in a particular experiment. How many measurements should she make?
Harris Text: Ch. 13: 1, 5, 10, 16, 19, 28, 36 ; Ch. 14: 2,
Solution to Problems