Answer:
The system loses 90 kJ of heat
Explanation:
We can answer the question by using the 1st law of thermodynamics, which states that:
where
is the change in internal energy of the system
is the heat absorbed by the system (positive if absorbed, negative if released by the system)
is the work done by the system (positive if done by the system, negative if done by the surrounding on the system)
In this problem, we have:
is the work done (negative, because it is done by the surrounding on the system)
is the increase in internal energy
Using the equation above, we can find Q, the heat absorbed/released by the system:
And the negative sign means that the system has lost this heat.
Answer:
This question is incomplete
Explanation:
This question is incomplete because of the absence of options. However, one material that is good candidate for conducting electricity without reacting with other materials is metallic vanadium dioxide. This is because of the inability of this electrical conductor to conduct heat (an unusual property for all other electrical conductors) and thus makes it difficult for it to react with other materials (since an increase in temperature increases possibility of a reaction).
Answer:
Explanation:
Given
Resistor A has length 
and Resistor B has Length 
and Resistance is given by
Considering 
and A to be constant thus
because 
(a)When they are connected in series
As the current in series is same and power is 
therefore 
as R is greater for second resistor
(b)if they are connected in Parallel
In Parallel connection Voltage is same
resistance of 2 is greater than 1 thus Power delivered by 1 is greater than 2
Answer:
0.08 ft/min
Explanation:
To get the speed at witch the water raising at a given point we need to know the area it needs to fill at that point in the trough (the longitudinal section), which is given by the height at that point.
So we need to get the lenght of the sides for a height of 1 foot. Given the geometry of the trough, one side is the depth <em>d</em> and the other (lets call it <em>l</em>) is given by:
since the difference between the upper and lower base is the increase in the base and we are only at halft the height.
Now we can calculate the longitudinal section <em>A</em> at that point:
And the raising speed <em>v </em>of the water is given by:
where <em>q</em> is the water flow (1 cubic foot per minute).
