Question

An experiment in which 44.00kJ of heat is added to a cube of metal with initial side length 1.00m and temperature 300.K is performed twice, once with a copper cube and once with a lead cube. Fill in the blanks with "<", ">", "=", "N/A". Select N/A only if a comparison is not possible.

The copper cube's initial volume is  the lead cube's.
The copper cube's initial temperature is  the lead cube's.
The copper cube's final temperature is  the lead cube's.
The copper cube's final volume is  the lead cube's.
The copper cube's final mass is  the lead cube's.
The copper cube's final internal energy is  the lead cube's.

Answer 1

Initial temperature and side lengths are same for both the cubes of metal. =>

a)The copper cube's initial volume is equal to the lead cube's.

b)The copper cube's initial temperature is equal to  the lead cube's.

c)sp heat capacity is the amount of heat requred to change the temp of a material by 1 degree or Kelvin

Sp heat of cu is 386  J/kg K and of lead is 128  J/kg K So, lead requires lesser heat to increase its temp. so, since both cubes get equal amount of heat , lead will have higher final temperature than copper.

The copper cube's final temperature is lesser than  the lead cube's.

d)linear expansion coeff is the increase in length of a material with increase in temp by 1 degree. coeff of volume expansion is 3 times linear expansion coeff and it is the increase in volume of a material with increase in temp by 1 degree

linear expansion coeff of cu is 16.5 ppm/°C and of Pb is 29.3 ppm/°C so, evidently lead will expand more on increase in temp also temp increase in this case is more for lead. so, undoubtedly, final volum of lead > cu

The copper cube's final volume is less than the lead cube's.

e)initial mass of cu = volume * density = 1m^3* 8950 kg/m^3 =8950 kg

final temp of cu = > 8950*386*(T-300) =44000 => T= 300.0127 K

initial mass of Pb = volume * density = 1m^3*11342 kg/m^3 =11342 kg

final temp of Pb => 11342*128*(T-300) = 44000 => T= 300.03 K

It is evident that the heating process increases their temperatures by small amoounts onlly and hence both of tem wont reach their boiling point hence the whole of the initial mass will remain after the process so, since initially, mass of lead is greater than that of copper, final masses will also have same relation

The copper cube's final mass is lesser than the lead cube's.

f)the internal energy chnge will be the heat suplied for both the blocks so since the heat supplied is same,  internal energy chnge will be same

The copper cube's final internal energy is equal to the lead cube's.