Deck 6: Fundamental Dimensions and Units

Question 1

The fundamental frequency of a vibrating guitar string is modeled by the following equation: where vibration frequency in Hertz length of string in meters string tension in Newtons string density
What is the appropriate unit for if the preceding equation is to be homogeneous in units?

Answer 1

Question 2

The amount of time it takes for an object bounce up and down through one complete cycle is called the "period" and is calculated using the following equation: where period in seconds mass of object in kilograms spring rate
What is the appropriate unit for k if the preceding equation is to be homogeneous in units?

Answer 2

Question 3

Which of the following are fundamental British Gravitational units?

A)seconds, meters, liters
B)pound force, seconds, feet
C)Newton, seconds, kilograms
D)seconds, kilograms, Kelvins
E)hours, meters, Watts

Answer 3

B

Question 4

Convert the information given in the table below from the U.S.customary units to SI units.

Question 5

Which of the following are fundamental SI units?

A)seconds, meters, liters
B)seconds, meters, grams
C)Newton, seconds, kilograms
D)seconds, kilograms, Kelvins
E)hours, meters, Watts

Question 6

Convert the information given in the table below from SI units to U.S.Customary units.

Question 7

What is the difference between "dimensions" and "units?"

Question 8

Dimension is a physical quantity, such as length, time, mass, or temperature, that makes it possible for us to communicate.

Question 9

Which of the following are U.S.Customary units?

A)gallons, yards, horsepower
B)barrels, Fahrenheit, Watts
C)acres, hectares, liters
D)cubic yards, Pascals, Joules

Question 10

Calculate the number of liters of water that will fit into an aquarium with dimensions:

Question 11

Convert the information given in the table below from the U.S.customary units to SI units.

Question 12

How many times does the average human heart beat during an average lifetime (75 years)?

Question 13

Convert the information given in the table below from SI units to the U.S.customary units.

Question 14

The friction force between two surfaces is modeled using the following equation: where friction force in N coefficient of friction normal force in N
What is the appropriate unit for if the preceding equation is to be homogeneous in units?

Question 15

Which of the following are fundamental dimensions:

A)area, volume, power, pressure, energy
B)temperature, time, mass, length
C)force, energy, power, weight
D)heat, power, power, weight
E)electric resistance, electrical voltage, electric power

Question 16

The speed of sound in a fluid can be calculated using the following equation: where speed of sound in bulk modulus fluid density in What is the appropriate unit for B if the preceding equation is to be homogeneous in units?

Question 17

The ice at a certain hockey rink is made by freezing water that is 3.81 cm deep.How many liters of water does it take? Approximate the rink as a by rectangle.

Question 18

Write the fundamental SI units adjacent to each of the fundamental dimension given.
Length _________
Temperature _________
Electrical Current _________
Time _________
Luminous intensity _________
Mass _________
Amount of a substance _________

Question 19

One slug is equal to

A)32.2 lbm
B)1 lbm
C)1/32.2 lbm
D)None of the above

Question 20

We need not only physical dimensions to describe our surroundings but also some way to scale or divide these physical dimensions.

Question 21

A 500 sheet rim of copy paper has a thickness of 2.25 inch.What is the average thickness of each sheet in mm?

A)0.11 mm
B)1.1 mm
C)11 mm
D)none of the above

Question 22

An engineering professor weighs 200 lbf.Express the mass and the weight of the professor in SI and U.S.Customary units.

Question 23

The Btu (British thermal unit) is defined as the amount of heat required to raise the temperature of 1 lbm of water by 1°F.If a home has a furnace that is rated at 1000 Btu/min what is this rating in kW?

A)17.584 kW
B)17584 kW
C)293 kW
D)0.293 kW

Question 24

Determine the number of significant digits for the following numbers:

Question 25

The conduction heat transfer rate through a wall is modeled by the following equation: where heat transfer rate in thermal conductivity of the wall area of the wall in wall thickness in steady-state temperature difference between the inside and the outside surfaces of the wall, in What is the appropriate unit for k if the preceding equation is to be homogeneous in units?

Question 26

The acceleration due to gravity at the surface of the moon is approximately 1/6 of the earth's.The acceleration due to gravity at the surface of moon is equal to:

A)1.6 ft/s2
B)64 in/s2
C)5.4 m/s2
D)none of the above

Question 27

Express the work done [work = (force)(distance)] by a 100 lbf force exerted over a distance of 50 ft using SI units.

Question 28

A motorcyclist who weighs 160 lbf accelerates his motorcycle at a rate of 10 ft/s2 over a distance of 100 yards in 5 seconds.Convert all of the values given to SI units.

Question 29

A one degree temperature difference in Celsius is equal to one degree temperature difference in Kelvin.

Question 30

A parking lot is long by wide.Express the area of the garden in m2and acres.

Question 31

The density of steel is approximately 7600 kg/m3.Express the density in BG and U.S.Customary units.

Question 32

A barrel can hold 42 gallons of oil.How many liters of oil are in the barrel?

A)15.9 liters
B)42 liters
C)159 liters
D)4.2 liters

Question 33

A one degree temperature difference in Fahrenheit is equal to one degree temperature difference in Rankine.

Question 34

The absolute pressure of a fluid point at a certain depth can be calculated using the following equation: where absolute pressure of the fluid atmospheric pressure density of fluid gravitational acceleration, depth of the point below the fluid surface What is the appropriate unit for if the preceding equation is to be homogeneous in units?

Question 35

The amount of heat needed to change the temperature of an object can be calculated using the following equation: where amount of heat in Joules (J) mass of object in kilograms (kg) specific heat of object change in temperature in °C
What is the appropriate unit for if the preceding equation is to be homogeneous in units?

Question 36

An individual running on a treadmill machine generated an average power of approximately 0.27 hp.Express this power in Watts.

Question 37

A swimming pool is 50 m long, 10 m wide and 3 m deep.Express the volume of the water in the swimming pool in ft3 and gallons.

Question 38

A one degree temperature difference in Fahrenheit is equal to one degree temperature difference in Celsius.

Question 39

The force between two charged particles can be calculated using the following equation: where force in Newtons (N)
k = electrostatic constant charge of particle #1 in Coulombs (C) charge of particle #2 in Coulombs (C) distance between particles in meters (m)
What is the appropriate unit for k if the preceding equation is to be homogeneous in units?

Question 40

When an aluminum cookie sheet is placed in an oven and heated up, it expands due to the temperature change.The change in area of the cookie sheet is modeled using the following equation: where change in area in original area in area coefficient of thermal expansion change in temperature in What is the appropriate unit for if the preceding equation is to be homogeneous in units?

Question 41

What is the SI unit for torque?

A)N.m
B)kg.m
C)N/m
D)kg/m

Question 42

What is the SI unit for angular velocity?

A)m/s
B)rad/s
C)cm/s
D)mm/s

Question 43

What is the SI unit for pressure?

A)Pa
B)N/m2
C)kg/m.s2
D)All of the above

Question 44

What is the SI unit for power?

A)W
B)J/S
C)kg.m2/s3
D)All of the above

Question 45

What is the SI unit for momentum?

A)kg.m/s
B)N.m/s
C)m/s2
D)m2/s