Order of Magnitude Estimates

These estimates may be helpful when you're trying to determine if your numerical answers makes sense.  They may also come in handy if you need to make an estimate or assumption in a problem.
 

Typical Electric Fields

Inside household wires	10-2 N/ C
In radio waves	10-1 N/ C
In the atmosphere	102 N/ C
In sunlight	103 N/ C
Near a charged plastic comb	103 N/ C
Under a thundercloud	104 N/ C
In a lightning bolt	104 N/ C
At the charged drum of a photocopier	105 N/ C
In an x-ray tube	106 N/ C
At the electron of a hydrogen atom	5 x 1011 N/ C
At the surface of an uranium nucleus	3 x 1021 N/ C

Typical Magnetic Fields

Inside human brain (due to nerve impulses)	10-13 T
Surface of the earth	0.5 x 10-4 T
Surface of the sun	10-2 T
Near a bar magnet	10-2 T
Inside a medical MRI unit	1.5 T
Strong laboratory magnet	2 T
Strong superconducting magnet	30 T

From mechanics-

Typical Distances

Diameter of the known universe	1026 m
From earth to the nearest galaxy (Andomeda, M31)	2 x 1022 m
Diameter of our galaxy	8 x 1020 m
From earth to the nearest star (that’s not our sun)	4 x 1016 m
From Pluto to the sun	6 x 1012 m
From earth to the sun	1.5 x 1011 m
Radius of the earth	6.4 x 106 m
Height of Mt. Everest	8848 m
Length of a football field	102 m
Height of a person	2 m
Diameter of a CD	0.12 m
Diameter of a period in our text	5 x 10-4 m
Diameter of a red blood cell	8 x 10-6 m
Diameter of a virus	2 x 10-8 m
Diameter of a hydrogen atom	10-10m
Diameter of a proton	2 x 10-15 m

Typical Masses

Galaxy	4 x 1041 kg
Sun	2 x 1030 kg
Earth	6 x 1024 kg
Space Shuttle	2 x 106 kg
747 airplane	3.5 x 105 kg
Elephant	5400 kg
Automobile	1200 kg
Person	70 kg
Bowling ball	7 kg
Baseball	0.15 kg
Honeybee	1.5 x 10-4 kg
Raindrop	2 x 10-5 kg
Red blood cell	10-13 kg
Virus	10-20 kg
Hydrogen atom	1.67 x 10-27 kg
Electron	9.11 x 10-31 kg

Typical Times

Age of the universe	4 x 1017 s
Age of the Earth	1.5 x 1017 s
Existence of the human species	6 x 1012 s
Human lifetime	2 x 109 s
One year	3 x 107 s
One day	8.6 x 104 s
Time between heartbeats	0.8 s
Collision time for batted ball	2 x10-3 s
One cycle of a visible light wave	2 x 10-15 s

Typical Speeds

Light	3 x 108 m/ s
Earth orbiting the sun	3 x 104 m/ s
Concorde airplane	710 m/ s
Terminal speed of a sky diver	60 m/ s
Pitched baseball	45 m/ s
Running cheetah	28 m/ s
Olympic sprinter	12 m/ s
Terminal speed of a raindrop	7 m/ s
Brisk walk	1.3 m/ s
Snail	10-3 m/ s
Human hair growing	3 x 10-9 m/ s
Continental drift	10-9 m/s

Typical Accelerations

Ultracentifuge	3 x 106 m/ s2
Baseball when batted	3 x 104 m/ s2
Car crashing into a wall at 60 mph	103 m/ s2
Bungee jump	30 m/ s2
Gravitational acceleration on surface of earth	9.8 m/ s2
Emergency stop in a car	8 m/ s2
Gravitational acceleration on surface of moon	1.7 m/ s2

Typical Forces

Saturn V rocket	3.4 x 107 N
Main engines of the shuttle	2 x 106 N
Pulling force of a locomotive	105 N
Weight of an adult	1000 N
Weight of an apple	1 N
Weight of an ant	1 x 10-3 N

Typical Energies

Annual US energy use	8 x 1019 J
Mt. St. Helens eruption	1018 J
Thunderstorm	1015 J
Jet aircraft moving at 500 mph	109 J
Energy released in the explosion of 100 pounds of TNT	2 x 108 J
Chemical energy in one gallon of gas	108 J
Chemical energy in a large pizza	2 x 107 J
Human food intake/ day	107 J
Car travelling at 60 mph	106 J
Energy required to melt an ice cube	104 J
Electrical energy used to light a 100W blub for 1 minute	6 x 103 J
Football linebacker running at a quarterback	4.5 x 103 J
Kinetic enegy of a person walking	50 J
Kinetic energy of a flying bee	2 x 10-3 J
Work to turn a page of a textbook	10-3 J
Kinetic energy of a moving snail	5 x 10-7 J
Energy required to break a bond in DNA	10-20 J