O bila avand masa m=2kg cade liber de la inaltimea h=20m fata de sol. Cand bila trece printr-un punct P energia potentiala a sistemului bila-Pamant este o treime din energia sa cinetica.(g=10N/kg) a) La ce inaltime fata de sol se gaseste punctul P?

b) Care este energia cinetica a bilei cand trece prin punctul P?

c) Care este viteza cu care corpul atinge solul?

As shown in fig. p3.64, a closed, rigid tank fitted with a fine-wire electric resistor is filled with refrigerant 22, initially at 2108c, a quality of 80%, and a volume of 0.01 m3. a 12-volt battery provides a 5-amp current to the resistor for 5 minutes. if the final temperature of the refrigerant is 408c, determine the heat transfer, in kj, from the refrigerant.

Which of the following are considered noble gases? a. bromine b. neon c. argon d. chlorine

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.