Answer
a) 229 K or -44$^{\circ}$ C
b) 76 K or -197$^{\circ}$ C
Work Step by Step
a) $T_{1}$ = (32+273) K = 305 K
Let's assume $V_{1}$ = 4 V
Then $V_{2}$ = 3 V (decreased by 25%)
According to Charles's Law, $\frac{V_{1}}{T_{1}}$ = $\frac{V_{2}}{T_{2}}$
Or $T_{2}$ = $\frac{V_{2}\times T_{1}}{V_{1}}$ = $\frac{3V\times305K}{4V}$ $\approx$ 229 K
b) Here only $V_{2}$ is changed.
$V_{2}$ = V if $V_{1}$ = 4V
$T_{2}$ = $\frac{V\times 305 K}{4V}$ $\approx$ 76 K
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