MCQ
A cylinder of $5$ litre capacity, filled with air at $N.T.P.$ is connected with another evacuated cylinder of $30$ litres of capacity. The resultant air pressure in both the cylinders will be ...... $cm$ of $Hg$
  • A
    $38.85$
  • B
    $21.85$
  • $10.85$
  • D
    $14.85$

Answer

Correct option: C.
$10.85$
c
Boyle's law states that $P_{1} V_{1}=P_{2} V_{2}$

Here, at $NTP$, pressure $=76 cm$ of $Hg = P _{1}$

$V _{1}=5 L$

$V _{2}=30 L +5 L$

Now

$P _{1} \times(5)= P _{2} \times(35)$

$P _{1}=7 P _{2}$

$P _{2}=76 / 7=10.8 cm$ of $Hg$

So, pressure in both cylender $=10.8 cm$

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