Question

Un muncitor a ridicat la etajul trei (cu inaltimeade10 m) un corp cu masa de 15 kg. Cu cit s-a marit energia potentiala a sistemului corp-Pamint?

Answer 1

$h=10 \ m \\ m=15 \ kg \\ g=10 \ N/kg \\ \boxed{\Delta E_p-?} \\ \bold{Rezolvare:} \\ \boxed{E_p=m \cdot g \cdot h} \ \ \ \ \ \ \ \ \ \ \ \ \ \boxed{\Delta E_p=E_{p2}-E_{p1}} \\ E_{p1}=0 \ J\\ E_{p2}=15 \ kg \cdot 10 \ N /kg \cdot 10 \ m \\ E_{p2}=150 \ N \cdot 10 \ m \\ E_{p2}=1 \ 500 \ J \\ \Delta E_p=1 \ 500 \ J-0 \ J \\ \Rightarrow \boxed{\Delta E_p=1 \ 500 \ J}$