BL :
Ta có : \(\left\{{}\begin{matrix}Q_{thu}=m_2.c_2.\Delta t_2=3.4200.\left(60-t_1\right)\\Q_{tỏa}=m_1.c_1.\Delta t_1=0,4.880.\left(60-t_1\right)\end{matrix}\right.\)
Theo pt cân bằng nhiệt ta có :
\(Q_{thu}=Q_{tỏa}\)
\(\Leftrightarrow756000-12600t_1=21120-352t_1\)
\(\Leftrightarrow756000-21120=12600t_1-352t_1\)
\(\Leftrightarrow734880=12248t_1\)
=> \(t_1=60^oC\)
~~~Team ko chắc đâu bạn ~~`