answer;
The hole in the center of the washer will expand
explanation;
<em>A flat metal washer is heated. As the washer's temperature increases, what happens to the hole in the center? A flat metal washer is heated. As the washer's temperature increases, what happens to the hole in the center? The hole in the center will remain the same size. Changes in the hole cannot be determined without know the composition of the metal. The hole in the center of the washer will expand. The hole in the center of the washer will contract.</em>
this is an example of area expansivity.
coefficient of area expansivity is change in area per area per degree rise in temperature
a=dA/(A*dt)
as the temperature rises , there will be volumetric and area expansivity on the body. volume also increases because of the intermolecular forces of attraction between the molecule is now getting apart.
Answer:
ΔH°comb=-5899.5 kJ/mol
Explanation:
First, consider the energy balance:
Where
is the calorimeter mass and
is the number of moles of the samples;
is the combustion enthalpy. The energy balance says that the energy that the reaction release is employed in rise the temperature of the calorimeter, which is designed to be adiabatic, so it is suppose that the total energy is employed rising the calorimeter temperature.
The product
is the heat capacity, so the balance equation is:

So, the enthalpy of combustion can be calculated:

I will be happy to solve any doubt you have.
Answer:
Final temperature will be 438.076 K
Explanation:
We have given temperature
Volume 
As there is no heat transfer so this is an adiabatic process
For and adiabatic process 
Here 
So 

A boat is floating in a small pond. the boat then sinks so that it is completely submerged. what happens to the level of the pond?
It increases!
Answer:i=300 mA
Explanation:
Given
inductance(L)=40 mH
Resistor(R)=
Voltage(V)=15 V
Time constant(
)=

current 

Current as a function of time is given by

i= 299.95 mA