Question

Rezolvati aceasta problema la fizica, sunt clasa a X-a si am nevoie de acesta problema rezolvata. Multumesc !​

Answer 1

$\displaystyle{ \nu = 1 \ mol }$

$\displaystyle{ monoatomic \rightarrow C_{V} = \frac{3}{2} R }$

$\displaystyle{ V_{1} = 16,62 \ l = 2 \cdot 8,31 \ l = 2 \cdot 8,31 \cdot 10^{-3} \ m^{3} }$

$\displaystyle{ p_{1} = 4 \cdot 10^{5} \ Pa }$

$\displaystyle{ trans. \ izocora \rightarrow \nu = constant, \ V = constant \rightarrow V_{1} = V_{2} = V }$

$\displaystyle{ p_{2} = p_{1} + 15\% = 115\% \cdot p_{1} }$

$\displaystyle{ p_{2} = \frac{115 \cdot 4 \cdot 10^{5}}{100} = 4,6 \cdot 10^{5} \ Pa }$

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$\displaystyle{ a) \ T_{1} = ? }$

$\displaystyle{ b) \ T_{2} = ? }$

$\displaystyle{ c) \ Q, L, \Delta U = ? }$

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a) $\displaystyle{ p_{1} \cdot V = \nu \cdot R \cdot T_{1} }$

$\displaystyle{ T_{1} = \frac{p_{1} \cdot V}{\nu \cdot R} = \frac{4 \cdot 10^{5} \cdot 2 \cdot 8,31 \cdot 10^{-3}}{1 \cdot 8,31} }$

$\displaystyle{ T_{1} = 8 \cdot 10^{2} = 800 \ K }$

b) $\displaystyle{ p_{2} \cdot V = \nu \cdot R \cdot T_{2} }$

$\displaystyle{ T_{2} = \frac{p_{2} \cdot V}{\nu \cdot R} = \frac{4,6 \cdot 10^{5} \cdot 2 \cdot 8,31 \cdot 10^{-3}}{1 \cdot 8,31} }$

$\displaystyle{ T_{2} = 4,6 \cdot 2 \cdot 10^{2} = 920 \ K }$

c) L = 0

$\displaystyle{ Q = \Delta U = \nu \cdot C_{V} \cdot \Delta T }$

$\displaystyle{ Q = \Delta U = \nu \cdot \frac{3}{2} R \cdot (T_{2} - T_{1}) }$

$\displaystyle{ Q = \Delta U = \frac{3}{2} \cdot (p_{2}V - p_{1}V) }$

$\displaystyle{ Q = \Delta U = \frac{3}{2} \cdot V \cdot (p_{2} - p_{1}) }$

$\displaystyle{ Q = \Delta U = \frac{3}{2} \cdot 2 \cdot 8,31 \cdot 10^{-3} \cdot (4,6 \cdot 10^{5} - 4 \cdot 10^{5}) }$

$\displaystyle{ Q = \Delta U = 3 \cdot 8,31 \cdot 10^{-3} \cdot 0,6 \cdot 10^{5} }$

$\displaystyle{ Q = \Delta U = 1,8 \cdot 8,31 \cdot 10^{2} }$

$\displaystyle{ Q = \Delta U = 180 \cdot 8,31 }$

Q = ΔU = 1495,8 J

Matei.