Exercise

An ideal monatomic gas is adiabatically compressed so that its final temperature is twice its initial temperature. What is the ratio of the final pressure to its initial pressure?
 

Why should a Carnot cycle have two isothermal two adiabatic processes? 

A hypothetical thermodynamic cycle is shown in the figure. Calculate the work done in 25 cycles. 

A gas contained in a cylinder fitted with a frictionless piston expands against a constant external pressure of $1 \mathrm{atm}$ from a volume of

$5 \mathrm{L}$ to a volume of $10 \mathrm{L}$. In doing so it absorbs $400 \mathrm{J}$ of thermal energy from its surroundings. Determine the change in internal energy of system.

A system releases $130 \mathrm{kJ}$ of heat while $109 \mathrm{kJ}$ of work is done on the system. Calculate the change in internal energy.

What sets the limits on efficiency of a heat engine? 

A Carnot refrigerator operates between $250 \mathrm{K}$ and $300 \mathrm{K}$. Calculate its coefficient of performance.

A resistor held in running water carries electric current. Treat the resistor as the system

(a) Does heat flow into the resistor?

(b) Is there a flow of heat into the water?

(c) Is any work done?

(d) Assuming the state of resistance to remain unchanged, apply the first law of thermodynamics to this process.