1. Physics and Physical Measurement
Chapter 1
Physics and Physical Measurement

2. 1.1 The Realm of Physics
State and compare quantities to the nearest order of magnitude.
Diameter of an atom= m
nucleus= 10-15m
quarks= m
Plank length= 10-35m

3. Must know general scientific measurements by memory
Pg. 4 Table 1.2, 1.3, 1.4

4. quark= possibly the smallest particle- hard to measure because they hide themselves inside protons and neutrons.
Question 1: If quark is 10-18m in size, what is the theoretical lower limit for time?

5. Round quantities to just their exponents to estimate quantities using simple addition and subtraction without using a calculator.
Question 2: If plank is smallest length what is the theoretical lower limit for time?

6. 1.1.2 Ranges of Distances, Masses, Times in the Universe
Distances: From 10-15m to 1025m ( sub-nuclear particle to the extent of visible universe)
Masses: From 10-30kg to 1050kg (electron to mass of universe)
Times: From 10-23s to 1018s (passage of light across nucleus to age of universe)

7. 1.1.3 State ratios of quantities as differences in orders of magnitude
Question 3: Ratio of diameter of atom to nucleus?
Proton and nucleus=about the same in diameter
Proton= 10-15m diameter

8. Units on the left hand side of the equation must be the same as the units on the right hand side. This is a way to check if equation is correct.
Question 4:

9. 1.1.4 Approximate values of everyday quantities to nearest order of magnitude
Question 5: What pressure do you exert of the ground standing on one foot?
HW: pg. 6-7 # 11,15,25,32,33 (Tsokos)