JEE Advanced 2014 Paper 1 Physics Q20

Physics · Thermodynamics

Problem

A thermodynamic system is taken from an initial state

i

with internal energy

U_i=100\,\mathrm{J}

to the final state

f

along two different paths

iaf

and

ibf

, as schematically shown in the figure. The work done by the system along the paths

af

ib

and

bf

are

W_{af}=200\,\mathrm{J}

W_{ib}=50\,\mathrm{J}

and

W_{bf}=100\,\mathrm{J}

respectively. The heat supplied to the system along the path

iaf

ib

and

bf

are

Q_{iaf}

Q_{ib}

and

Q_{bf}

respectively. If the internal energy of the system in the state

b

U_b=200\,\mathrm{J}

and

Q_{iaf}=500\,\mathrm{J}

, the ratio

Q_{bf}/Q_{ib}