PE = mgh
where
m = mass
g = acceleration due to gravity
h = height
C. a truck rolling down hill
The smaller body will have greater temperature change.
<h3><u>Explanation</u>:</h3>
Temperature is defined as the degree of hotness or coldness of a body. The relationship of the temperature with heat is described as
Q =m c dT.
Where Q is the heat content
m is the mass of body
c is the specific heat of body
dT is the temperature change of body.
Here the bodies are made up of same substance, so specific heat is same. The mass of bigger body is M and smaller body is m.
So the temperature change of the body will be dependent on the mass of the body. Heat loss by one body will be equal to heat gained by the other.
So M dT1 = mdT2.
So, M/m = dT2 / dT1.
So the the smaller body will be suffering higher temperature change.
Answer:
I think all will display the same value
Explanation:
Sorry if this is wrong
Answer:
Before giving an injection, a nurse dabs some alcohol onto the patient`s arm. This makes the patient`s skin feels cold. Explain Why ?
<em> Evaporative cooling makes this to be possible</em>
Explanation:
The concept
For a liquid to evaporate, there must be a breakdown of the bond between the molecules of the liquid. These bonds are broken when the molecules gain heat energy. So basically evaporation occurs when the molecules of the substance gain energy in form of heat.
Our Scenario
Just like the way our body excretes sweat on a sunny day, alcohol takes energy from the skin to evaporate. The bond holding the molecules of alcohol breaks faster due to its low boiling point and this account why it evaporates faster. The sudden evaporation of alcohol when dabbed on the skin results in quick utilization of heat energy making the skin feel cold for some time.
The utilization of heat energy from the skin results in evaporation cooling which makes the skin feel colder.
