It's about five-and-a-half times as heavy as a Tennis Ball
In other words, 0.000000000310 megatonnes is 5.370 times the weight of a Tennis Ball, and the weight of a Tennis Ball is 0.1860 times that amount.(ITF Standard; for Type 2 ball)
Per International Tennis Federation standard, regulation tennis balls must weigh about 0.00000000005770 megatonnes. Competition balls are also tested for bounce height, with the standards requiring that a ball dropped from 254 cm must bounce back to a height of 135 cm to 147 cm.
It's about six-and-a-half times as heavy as a Golf Ball
In other words, 0.000000000310 megatonnes is 6.7490 times the weight of a Golf Ball, and the weight of a Golf Ball is 0.14820 times that amount.(per R&A USGA Rules of Golf; maximum rule weight)
According to the Rules of Golf (as approved by the United States Golf Association and the Rules Committee of the Royal and Ancient Golf Club of Saint Andrews), golf balls must weigh no more than 0.000000000045930 megatonnes. Golf balls are not required to have the familiar dimpled pattern, but the design has been popular since its invention in 1905 because it reduces drag while increasing lift.
It's about one-tenth as heavy as a Chihuahua
In other words, 0.000000000310 megatonnes is 0.1380 times the weight of a Chihuahua, and the weight of a Chihuahua is 7.250 times that amount.(a.k.a. Chihuahue(o) (FCI standard)
The F&d&ration Cynologique Internationale (FCI) calls for Chihuahuas to weigh about 0.000000002250 megatonnes. Relative to their body sizes, Chihuahuas have the largest brain size of any dog breed.
It's about one-tenth as heavy as a Brick
In other words, 0.000000000310 megatonnes is 0.110 times the weight of a Brick, and the weight of a Brick is 9.10 times that amount.(Standard, traditional face brick - 1,900 cu. cm (120 cu. in))
A standard, traditional face brick weighs an average of 0.00000000290 megatonnes. The steeple of the Church of St. Martin in Landshut, Germany is said to be the tallest brick tower in the world at a height of 130.6 m (428.5 ft) and was constructed using an estimated 650,000 bricks.
It's about nine times as heavy as a Light Bulb
In other words, 0.000000000310 megatonnes is 9.10 times the weight of a Light Bulb, and the weight of a Light Bulb is 0.110 times that amount.(a.k.a. lamp) (for A19-size, 60w, incandescent bulb by Bulbrite; package weight)
A standard, sixty-watt light bulb weighs about 0.0000000000340 megatonnes. The tightly-coiled filament inside a bulb of this size would measure about 579mm if uncoiled and stretched out.
It's about thirteen times as heavy as a Battery (AA)
In other words, the weight of a Battery (AA) is 0.077 times 0.000000000310 megatonnes.(Alkaline)
An "AA" size battery weighs 0.0000000000240 megatonnes. AA batteries came into common use during World War II and were given their name by the American National Standards Institute (ANSI) Committee C18 because they were smaller than the "A" size batteries which were invented first.
It's about one-fifteenth as heavy as a Cat
In other words, the weight of a Cat is 10 times 0.000000000310 megatonnes.(Felis catus) (Domestic; healthy weight)
The average domestic cat should weigh about 0.00000000500 megatonnes. Cats are known for their righting reflex, which allows them to land on their feet and survive falls from heights of 1 m up to about 21 m.