Conduction: In the conduction, the heat is transferred from the hotter body to the colder body until the temperature on both bodies are equal.
In thermal equilibrium, there is no heat transfer as the heat is transferred till the temperature on the bodies are not same.
In the given problem, an iron bar at 200°C is placed in thermal contact with an identical iron bar at 120°C in an isolated system. After 30 minutes, the thermal equilibrium is attained. Then, the temperature on both iron bars are equal.Both iron bars are at 160°C in an isolated system.
But in an open system, the temperatures of the iron bars after 30 minutes would be less than 160°C. There will be heat lost to the surrounding. The room temperature is 25°C. There will be exchange of the heat occur between the iron bars and the surrounding. But It would take more than 30 minutes for both iron bars to reach 160°C because heat would be transferred less efficiently.
Answer:
A and C
Explanation:
The term formula unit is use to indicate Simple-Whole Ratios of ions in a compound. KEY WORD! RATIO!
Answer:The correct answer is option C.
Explanation;
Water has unique property that is, it expands on freezing.Which is the reason for less density of ice than water. The cracking of the bottle was due to the expansion of water (present inside the bottle) on freezing.
Generally, density is inversely proportional to the volume of the substance.
![Density=\frac{Mass}{Volume}](https://tex.z-dn.net/?f=Density%3D%5Cfrac%7BMass%7D%7BVolume%7D)
![Density\propto \frac{1}{Volume}](https://tex.z-dn.net/?f=Density%5Cpropto%20%5Cfrac%7B1%7D%7BVolume%7D)
As we know ,that water expands on freezing which means that volume increases. And with increase in volume of density decreases.
Hence, the correct answer is option C.
Answer:
When white glue is in the bottle, there's not enough air inside the bottle to cause the water to evaporate to make the glue sticky. Basically, the bottle holds the glue from the air and keeps the glue from going everywhere.