Question

reviewing main ideas

1. indicate which of the following physics symbols denote units and which denote variables or quantities.

a. c b. c c. c d. t e. t f. t

1. determine the units of the quantity described by each of the following combinations of units:

a. kg(m/s)(1/s) b. (kg/s)(m/s²)
c. (kg/s)(m/s)² d. (kg/s)(m/s)

1. which of the following is the best order - of - magnitude estimate in meters of the height of a mountain?

a. 1 m b. 10 m c. 100 m d. 1000 m
interpreting graphics

1. which graph in figure 3.6 best matches the data?

volume of air (m³) mass of air (kg)
0.50 0.644
1.50 1.936
2.25 2.899
4.00 5.159
5.50 7.096
critical thinking

1. which of the following equations best matches the data from item 4?

a. (mass)² = 1.29 (volume) b. (mass)(volume) = 1.29
c. mass = 1.29 (volume) d. mass = 1.29 (volume)²

Explanation:

1.

Step1: Recall physics symbols

In physics, uppercase and lowercase letters can have different meanings for units and variables.

• C (coulomb) is a unit of electric - charge.
• c (speed of light in vacuum) is a variable.
• C (capacitance) is a variable.
• t (time) is a variable.
• T (tesla) is a unit of magnetic - field strength.
• T (temperature) is a variable.

Step1: Use unit - multiplication rules

For a. $kg(m/s)(1/s)=kg\cdot m/s^{2}$, which is the unit of force (newton, N).

Step2: For b

$(kg/s)(m/s^{2})=kg\cdot m/s^{3}$, which is a non - standard derived unit.

Step3: For c

$(kg/s)(m/s)^{2}=(kg/s)(m^{2}/s^{2}) = kg\cdot m^{2}/s^{3}$, which is a non - standard derived unit.

Step4: For d

$(kg/s)(m/s)=kg\cdot m/s^{2}$, which is the unit of force (newton, N).

Step1: Consider real - world mountain heights

Mountains are very tall. 1 m and 10 m are too short for a mountain. 100 m is also relatively short for a typical mountain. Mountains like Mount Everest are several kilometers high. The best order - of - magnitude estimate among the options is 1000 m.

Answer:

a. Unit
b. Variable
c. Variable
d. Variable
e. Unit
f. Variable

2.