Which of the following statements are IMPOSSIBLE?

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The discussion revolves around identifying impossible statements related to physics concepts. Participants agree that a hydraulic system cannot have different pressures at the small and big pistons, and a container cannot displace more liquid than its volume. The possibility of a substance melting at a constant temperature is debated, with references to phase transitions. The concept of temperature measurement in a vacuum chamber is also discussed, emphasizing that a perfect vacuum does not exist and questioning the assumption of no air present. Overall, the thread highlights misconceptions about pressure, buoyancy, and thermodynamics in various scenarios.
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Homework Statement



Which of the following statements are IMPOSSIBLE? Choose all that apply.

___A perfectly functioning hydraulic had a pressure of 36 Pa in the fluid near the small piston and a pressure of 37 Pa in the fluid near the big piston.
___A 35 L container displaced 42 L of orange juice when partially submerged.
___A substance underwent melting during which its temperature remained constant at 33 °C.
___A 37 N brick was fully submerged in water. The buoyant force on the brick was 48 N. As a direct result, the brick was neutrally buoyant.
___Last Friday, the Sun heated the Moon via convection.
___The temperature inside a vacuum chamber was measured to be 3 °C.



Homework Equations





The Attempt at a Solution



Based on what I have learned this is my attempt:

_x__A perfectly functioning hydraulic had a pressure of 36 Pa in the fluid near the small piston and a pressure of 37 Pa in the fluid near the big piston.
_x__A 35 L container displaced 42 L of orange juice when partially submerged.
___A substance underwent melting during which its temperature remained constant at 33 °C.
_x__A 37 N brick was fully submerged in water. The buoyant force on the brick was 48 N. As a direct result, the brick was neutrally buoyant.
_x__Last Friday, the Sun heated the Moon via convection.
___The temperature inside a vacuum chamber was measured to be 3 °C.
 
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Try defining temperature in a perfect vacuum.
 
So what is your question? Can you provide reasoning why the ones you marked are impossible?
 
Saraphim said:
Try defining temperature in a perfect vacuum.
A vacuum chamber does not necessarily hold a perfect vacuum, in fact it never does, not to mention black body radiation.
 
kuruman said:
A vacuum chamber does not necessarily hold a perfect vacuum, in fact it never does, not to mention black body radiation.

You are of course right. I'm too used to idealized questions. :)
 
well a vacuum chamber has no air,
so would it be 0 K meaning their is no motion in the particles...

so the vacuum one would be impossible too?

My other question is:
is this possible:
A substance underwent melting during which its temperature remained constant at 33 °C
 
traveler7 said:
well a vacuum chamber has no air,
so would it be 0 K meaning their is no motion in the particles...
I know plenty of vacuum chambers that have air in them. The statement of the question is
"The temperature inside a vacuum chamber was measured to be 3 °C." There is no mention whether there is gas in it or not. Why do you assume that it contains a perfect vacuum which doesn't even exist?
My other question is:
is this possible:
A substance underwent melting during which its temperature remained constant at 33 °C
What happens to the temperature of a substance when it undergoes a phase transition from solid to liquid? Think of melting ice.
 
I asked my teacher about a vacuum chamber today and he said that it contains no air

and thanks for the other one I understand it now
 
OK. Assume that the vacuum chamber has not even a single molecule of air. You stick a mercury thermometer in it. Originally the thermometer reads 3 oC. Will the mercury column drop and indicate a lower temperaure?
 
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