The time required for the light to reach Earth from the Sun is to be calculated. Concept introduction: Dimensional analysis is a way to convert the units of measurement. In order to convert one unit to another, one needs to know the relationship between those units. These relationships are called conversion factors. Dimensional analysis is used to set up and solve a unit conversion problem using conversion factors. Conversion factor is a fraction obtained from a relationship between the units. It is written as a ratio, and can be inverted to give two conversion factors for every relationship. 1 mi = 1609.34 m , to convert mi to meter, the conversion factor is 1609.34 m 1 mi . 1 min = 60 s , to convert minute to second, the conversion factor is 60 s 1 min . speed = distance time and time = distance speed .
The time required for the light to reach Earth from the Sun is to be calculated. Concept introduction: Dimensional analysis is a way to convert the units of measurement. In order to convert one unit to another, one needs to know the relationship between those units. These relationships are called conversion factors. Dimensional analysis is used to set up and solve a unit conversion problem using conversion factors. Conversion factor is a fraction obtained from a relationship between the units. It is written as a ratio, and can be inverted to give two conversion factors for every relationship. 1 mi = 1609.34 m , to convert mi to meter, the conversion factor is 1609.34 m 1 mi . 1 min = 60 s , to convert minute to second, the conversion factor is 60 s 1 min . speed = distance time and time = distance speed .
Solution Summary: The author explains how to calculate the time required for the light to reach Earth from the Sun. Dimensional analysis is a way to convert the units of measurement.
Definition Definition Rate at which light travels, measured in a vacuum. The speed of light is a universal physical constant used in many areas of physics, most commonly denoted by the letter c . The value of the speed of light c = 299,792,458 m/s, but for most of the calculations, the value of the speed of light is approximated as c = 3 x 10 8 m/s.
Chapter 1, Problem 60QP
Interpretation Introduction
Interpretation:
The time required for the light to reach Earth from the Sun is to be calculated.
Concept introduction:
Dimensional analysis is a way to convert the units of measurement. In order to convert one unit to another, one needs to know the relationship between those units. These relationships are called conversion factors. Dimensional analysis is used to set up and solve a unit conversion problem using conversion factors.
Conversion factor is a fraction obtained from a relationship between the units. It is written as a ratio, and can be inverted to give two conversion factors for every relationship.
1 mi=1609.34 m, to convert mi to meter, the conversion factor is 1609.34 m1 mi.
1 min=60 s, to convert minute to second, the conversion factor is 60s1min.
(a
4 shows scanning electron microscope (SEM) images of extruded
actions of packing bed for two capillary columns of different diameters,
al 750 (bottom image) and b) 30-μm-i.d. Both columns are packed with the
same stationary phase, spherical particles with 1-um diameter.
A) When the columns were prepared, the figure shows that the column with
the larger diameter has more packing irregularities. Explain this observation.
B) Predict what affect this should have on band broadening and discuss your
prediction using the van Deemter terms.
C) Does this figure support your explanations in application question 33?
Explain why or why not and make any changes in your answers in light of
this figure.
Figure 4 SEM images of
sections of packed columns
for a) 750 and b) 30-um-i.d.
capillary columns.³
fcrip
= ↓ bandwidth Il temp
32. What impact (increase, decrease, or no change) does each of the following conditions have on the individual
components of the van Deemter equation and consequently, band broadening?
Increase temperature
Longer column
Using a gas mobile phase
instead of liquid
Smaller particle stationary phase
Multiple Paths
Diffusion
Mass Transfer
34. Figure 3 shows Van Deemter plots for a solute molecule using different column inner diameters (i.d.).
A) Predict whether decreasing the column inner diameters increase or decrease bandwidth.
B) Predict which van Deemter equation coefficient (A, B, or C) has the greatest effect on increasing or
decreasing bandwidth as a function of i.d. and justify your answer.
Figure 3 Van Deemter plots for hydroquinone using different column inner diameters (i.d. in μm). The data was
obtained from liquid chromatography experiments using fused-silica capillary columns packed with 1.0-μm particles.
35
20
H(um)
큰 20
15
90
0+
1500
100
75
550
01
02
594
05
μ(cm/sec)
30
15
10