- #1
dhruv96patel
- 3
- 0
In a barometer where a tube filled with mercury is inverted in dish filled with mercury, the mercury in the tube is suspended/rises to 760 mm mark. I read this is due to pressure of weight of mercury being equal to pressure of atmosphere.
My question is that, if i were to take the tube out of dish, will the mercury still stay in as atmosphere pressure has not changed.
Whats the physics behind pipettes in which the liquid stays suspended and does not flow out even when its removed from the dish?
For this, my view of pressure is that in barometer, mercury molecules exposed to surface are under force of atmosphere and mercury molecules exert same force back and consequently have same pressure through out mercury in dish. When the tube containing mercury is put in dish, the mercury in tube applies force to mercury in dish and force of mercury in tube is greater. Thus, mercury flows out until its mass decreases enough so that force of mercury in tube equals that of mercury in dish. And this seems to happen when mercury is 760 mm high in tube at atmospheric pressure.
If my microscopic view is flawed, please correct it. And answer my question according to correct microscopic view of pressure.
My question is that, if i were to take the tube out of dish, will the mercury still stay in as atmosphere pressure has not changed.
Whats the physics behind pipettes in which the liquid stays suspended and does not flow out even when its removed from the dish?
For this, my view of pressure is that in barometer, mercury molecules exposed to surface are under force of atmosphere and mercury molecules exert same force back and consequently have same pressure through out mercury in dish. When the tube containing mercury is put in dish, the mercury in tube applies force to mercury in dish and force of mercury in tube is greater. Thus, mercury flows out until its mass decreases enough so that force of mercury in tube equals that of mercury in dish. And this seems to happen when mercury is 760 mm high in tube at atmospheric pressure.
If my microscopic view is flawed, please correct it. And answer my question according to correct microscopic view of pressure.