It's about 150 times as heavy as a Human Heart
It's about one-two-hundred-fiftieth as heavy as an Anchor of a Cruise Ship
In other words, 50 kilograms is 0.00442 times the weight of an Anchor of a Cruise Ship, and the weight of an Anchor of a Cruise Ship is 226 times that amount.(for QE2 forward anchor, a.k.a. RMS Queen Elizabeth 2)
Each of the forward anchors of the RMS Queen Elizabeth 2 weighs 11,300 kg. The anchor of the QE2 now sits in front of the Holyrood Church in Southampton, England, United Kingdom, along a pedestrian tourist route known as "the QE2 mile."
It's about 300 times as heavy as a Hamster
In other words, the weight of a Hamster is 0.003 times 50 kilograms.(for Syrian hamster, a.k.a. golden hamster, a.k.a. Mesocricetus auratus; adult)
An adult Syrian hamster has a typical weight of about 0.20 kilograms. Known for transporting food in the pouches of their cheeks so that they can bury it later, some hamsters can store up to 25 kg of food in their borrows.
It's about 300 times as heavy as a Billiard Ball
In other words, 50 kilograms is 306.730103909390 times the weight of a Billiard Ball, and the weight of a Billiard Ball is 0.0032601951593751 times that amount.(American-style, WPA specifications)
Per the World Pool-Billiard Association, a billiard ball weight must weigh between 0.15592237718750 kilograms and 0.170097138750 kilograms. According to legend, the difficulty in obtaining elephant ivory for the manufacture of billiard balls in the 19th century inspired the search for a replacement material, which led to the development of the first industrial plastic.
It's about 300 times as heavy as a Puck (Hockey)
In other words, 50 kilograms is 306.730103909390 times the weight of a Puck (Hockey), and the weight of a Puck (Hockey) is 0.0032601951593751 times that amount.(Ice hockey)
A standard ice hockey puck weighs between 0.15592237718750 kilograms and 0.170097138750 kilograms. Hockey pucks can be shot or passed at speeds of up to 160 kph (99 mph) during games.
It's about 350 times as heavy as a Baseball
In other words, 50 kilograms is 344.136214142250 times the weight of a Baseball, and the weight of a Baseball is 0.0029058261203125 times that amount.(MLB rules)
Per Major League Baseball rules, a baseball must weigh between 0.1417476156250 kilograms and 0.148834996406250 kilograms. A major league pitcher can throw a baseball at up to 150 kph (91 mph) (with a fastball pitch), with record-setting pitches as fast as 171 kph (106 mph).
It's about 350 times as heavy as a Battery (D)
In other words, the weight of a Battery (D) is 0.0027 times 50 kilograms.(Alkaline)
A "D" size battery weighs 0.1350 kilograms. The D size battery is the oldest of the modern battery sizes, first invented by the National Carbon Company in 1898.