1. The density of an object is defined as
a. the volume occupied by each unit of mass.
b. the amount of mass for each unit of volume.
c. the weight of each unit of volume.
d. the amount of the substance that has unit volume and unit mass.
e. the amount of the substance that contains as many particles as 12 grams of the carbon-12 isotope.
ANSWER: b
POINTS: 1
DIFFICULTY: Easy
REFERENCES: 1.1 Standards of Length, Mass, and Time
HAS VARIABLES: False
2. One mole of the carbon-12 isotope contains 6.022 × 1023 atoms. What volume in m3 would be needed to store one mole
of cube-shaped children's blocks 2.00 cm long on each side?
a. 4.8 × 1018
b. 1.2 × 1022
c. 6.0 × 1023
d. 1.2 × 1024
e. 4.8 × 1024
ANSWER: a
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.1 Standards of Length, Mass, and Time
HAS VARIABLES: False
3. John and Linda are arguing about the definition of density. John says an object with a greater mass than another also
has a greater density. Linda says it is impossible to compare the densities of the two objects without also knowing their
volumes. Which one, if either, is correct?
a. They are both wrong.
b. John is correct, but Linda is wrong.
c. John is wrong, but Linda is correct.
d. They are both correct.
e. There is not enough information given to determine who is correct.
ANSWER: c
POINTS: 1
DIFFICULTY: Easy
REFERENCES: 1.1 Standards of Length, Mass, and Time
HAS VARIABLES: False
4. The standard kilogram is a platinum-iridium cylinder 39 mm in height and 39 mm in diameter. What is the density of
the material?
ANSWER: 21 464 kg/m3
POINTS: 2
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,Chapter 1 Physics and Measurement
DIFFICULTY: Average
REFERENCES: 1.1 Standards of Length, Mass, and Time
HAS VARIABLES: False
5. A 2.00-m by 3.00-m plate of aluminum has a mass of 324 kg. What is the thickness of the plate? (The density of
aluminum is 2.70 × 103 kg/m3.)
ANSWER: 2.00 cm
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.1 Standards of Length, Mass, and Time
HAS VARIABLES: False
6. What is the mass of air in a room that measures 5.0 m × 8.0 m × 3.0 m? (The density of air is 1/800 that of water).
ANSWER: 150 kg
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.1 Standards of Length, Mass, and Time
HAS VARIABLES: False
7. The term occurs in Bernoulli's equation, with ρ being the density of a fluid and v its speed. The dimensions of
this term are what?
a. M-1L5T2
b. MLT2
c. ML-1T-2
d. M-1L9T-2
e. M-1L3T-2
ANSWER: c
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.3 Dimensional Analysis
HAS VARIABLES: False
8. Which of the following quantities has the same dimensions as kinetic energy, ?
Note: [a] = [g] = LT-2; [h] = L and [v] = LT-1.
a. ma
b. mvx
c. mvt
d. mgh
e. mgt
ANSWER: d
POINTS: 2
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,Chapter 1 Physics and Measurement
DIFFICULTY: Average
REFERENCES: 1.3 Dimensional Analysis
HAS VARIABLES: False
9. The quantity with the same units as force times time, Ft, with dimensions MLT-1 is what?
a. mv
b. mvr
c. mv2r
d. ma
e.
ANSWER: a
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.3 Dimensional Analysis
HAS VARIABLES: False
10. The equation for the change of position of a train starting at x = 0 m is given by . What are the
dimensions of b?
a. T−3
b. LT−3
c. LT−2
d. LT−1
e. L−1T−1
ANSWER: b
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.3 Dimensional Analysis
HAS VARIABLES: False
11. Spike claims that dimensional analysis shows that the correct expression for change in velocity, , is
, where m is mass, t is time, and F is the magnitude of force. Carla says that can't be true because the
dimensions of force are . Which one, if either, is correct?
a.
Spike, because .
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, Chapter 1 Physics and Measurement
b.
Spike, because .
c.
Carla, because .
d.
Carla, because .
e.
Spike, because the dimensions of force are .
ANSWER: c
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.3 Dimensional Analysis
HAS VARIABLES: False
12. Which one of the quantities below has dimensions equal to ?
a. mv
b. mv2
c.
d. mrv
e.
ANSWER: c
POINTS: 2
DIFFICULTY: Average
REFERENCES: 1.3 Dimensional Analysis
HAS VARIABLES: False
13. Which quantity has dimensions equal to [MLT-1].
a. mr
b. mvr
c. ma
d. mat
e.
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