Diameter6.7 hundredths m
17.1 millionthsAkashi Kaikyo spans
136 billionthsLake Michigan lengths
1.9 tenthsViolins
6.54-6.86 cm per ITF regulations; ~6.7 cm typical
Photo by Ben Hershey on Unsplash
Tennis Ball
The fuzzy yellow sphere of athletic agony/Everyday Objects
A regulation tennis ball is a hollow rubber sphere covered in bright yellow felt, pressurized with air or nitrogen to give it a consistent bounce. The ITF mandates that a ball dropped from 2.54 meters must bounce to between 1.35 and 1.47 meters. The yellow color was adopted in 1972 because it showed up better on color television. Dogs consider them the single greatest invention in human history.
Measurements
Mass5.8 hundredths kg
193 trillionthsSupertanker loads
1.9 hundredthsLabrador puppies
1.7 hundredthsNewborn babies
56.0-59.4 g per ITF regulations
Fastest serve recorded73.2 m/s
7.01Usain Bolts
2 tenths9mm bullets
Sam Groth, 2012; 263.4 km/h (ATP-recognized record is lower)
Bounce height1.4 m
140 billionHard X-ray wavelengths
56,000Pollen grain widths
When dropped from 2.54 m; ITF requires 1.35-1.47 m
Impact force (serve)700 N
1.4 thousandthsLocomotive pulls
3.5Bicycle brakes
3.5 hundredthsHydraulic jacks
Approximate peak force on a 60 m/s serve impact
Internal pressure82,737 Pa
3.8 tenthsCar tires
762 millionthsMariana Trenches
~12 psi gauge pressure inside a new ball