Mathematical and Physical Journal
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Problem G. 746. (May 2021)

G. 746. Birds sit in the closed cargo hold of a truck, carrying birds. When the vehicle horn honks loudly, the birds get frightened. Does the total weight of the truck and the birds increase, decrease or remain unchanged when the birds fly off?

(3 pont)

Deadline expired on June 15, 2021.


Sorry, the solution is available only in Hungarian. Google translation

Megoldás. Amikor a madarak felreppennek, a rendszer tömegközéppontja függőlegesen felfelé gyorsul, emiatt a súly (a talajt nyomó \(\displaystyle G\) erő) megnő.

\(\displaystyle G-mg=ma,\qquad\text{tehát}\qquad G=mg+ma>mg.\)


Statistics:

25 students sent a solution.
3 points:Bacsó Dániel, Buzási-Temesi Imre, Czirók Tamás, Dancsák Dénes, Fehérvári Donát, Josepovits Gábor, Patricia Janecsko, Sebestyén József Tas, Vágó Botond, Waldhauser Miklós, Wórum Soma.
2 points:Cynolter Dorottya, Hegedűs Máté Miklós, Jeney Zsolt, Kovács Dorina , Láng Erik, Marozsi Lenke Sára, Országh Júlia, Veszprémi Rebeka Barbara.
1 point:6 students.

Problems in Physics of KöMaL, May 2021