Water is being heated in a closed pan on top of a range while being stirred by a paddle wheel. during the process, 30 kj of heat is transferred to the water and 5 kj of heat is lost to the surrounding air. the paddle-wheel work amounts to 500 n·m. determine the final energy of the system if its initial energy is 19.5 kj.

U₂=45 kJ

Explanation:

Given Data

Initial Energy U₁=19.5 kJ

Qin=30 kJ

Win=500 N.m

Qout= 5 kJ

To find

Final energy U₂

Solution

From The first law of thermodynamic

ΔE = Ein - Eout + ΔQ -ΔW

or

U₂=U₁+Qin+Win-Qout

where

U₂ is final energy

U₁ is initial energy

q = energy transferred as heat to a system

w = work done on a system

U₂=(19.5+30+500×10⁻³-5) kJ  

U₂=45 kJ

as technology advances, new experiments often expose problems in accepted theories. c

hope i

-lavira: )

hi there!

your question asks at which segment does freezing occur.

since we're talking about water, the freezing point of water will be 32 degrees fahrenheit or below.

hope this ! ~