Question

What is the height of mercury which exerts the same pressure as 20cm of water column? take density of mercury as 13.6 g/cc

Answer 1

Given: pressure exerted by Mercury column,
Pm =hm*dm*g (say)
pressure exerted by water column,
Pw=hw*dw*g(say)
but , Pm=Pw
=> hm*dm=hw*dw
or. hm=hw*dw/ dm
putting the values, 20*0.02*1000/13.6*1000
Answer = 0.0148 metre
i think this question will be solved like this.

Answer 2

Answer:

Explanation:

Solution :-

Pressure exerted by mercury columm,

P(m) = h(m) d(m) g(say)

Pressure exerted by water columm,

P(w) = h(w) d(w) g(say)

Where the symbols have their respective meaning,

But, P(m) = P(w)

⇒ h(m) d(m) = h(w) d(w)

⇒ h(m) = h(w) d(w)/d(m)

⇒ h(m) = 20 × 10⁻² × 10³/13.6 × 10⁻²

⇒ h(m) = 1.48 × 10⁻² m.

Hence, the height of mercury which exerts the same pressure is 1.48 × 10⁻² m.