Question

determinati temperatura pana la care se incalzesc 6l de apa,aflate la 17 grade C,prin arderea a 40g de benzina.Pierderele de caldura se neglijeaza.

Answer 1

$Q_p=|Q_c|\\Q_p=\rho_aV_ac_a(t_2-t_1),\text{ unde } t_1 = 17\:grade\\|Q_c|=q_bm_b, \text{ unde } q_b = 45\cdot 10^6 \frac{J}{kg}$
$\implies q_bm_b=\rho_aV_ac_at_2-\rho_aV_ac_at_1\\\implies t_2=\frac{\rho_aV_ac_at_1+q_bm_b}{\rho_aV_ac_a}\\t_2=t_1+\frac{q_bm_b}{\rho_aV_ac_a}$
$t_2\approx 88,6845878136\:^{o}C$