The temperature at the surface of the Sun is approximately $5700 \mathrm{~K}$, and the temperature at the surface of the Earth is approximately $290 \mathrm{~K}$. What entropy change occurs when $1000 \mathrm{~J}$ of energy is transferred by radiation from the Sun to the Earth?

The performance of a refrigerator or heat pump is described by a "coefficient of performance" defined as $K=Q_c / W$. What is the coefficient of performance for our Carnot heat pump?

A refrigerator has a coefficient of performance equal to 5.00. The refrigerator takes in 120 J of energy from a cold reservoir in each cycle. Find (a) the work required in each cycle and (b) the energy expelled to the hot reservoir.

Two electromagnetic waves are represented below. (a) Which wave has the higher frequency? (b) Which wave represents a more intense beam of light? (c) Which wave represents blue light, and which represents red light?

On the outbound leg of 400 miles, the plane flew at a moderate speed. On the trip back (also 400 miles), the pilot doubled the speed of the plane. How fast did the plane travel on the outbound leg if the total traveling time was 6 hours?

A thermodynamic system undergoes a process in which its internal energy decreases by $500 \mathrm{~J}$. If at the same time $220 \mathrm{~J}$ of work is done on the system, find the energy transferred to or from it by heat.

A thermodynamic system undergoes a process in which its internal energy decreases by 500 J. Over the same time interval, 220 J of work is done on the system. Find the energy transferred from it by heat.

A $1.0-\mathrm{kg}$ block of aluminum is heated at atmospheric pressure so that its temperature increases from $22^{\circ} \mathrm{C}$ to $40^{\circ} \mathrm{C}$. Find (b) the energy $Q$ added to the aluminum

Gas in a container is at a pressure of 1.5 atm and a volume of 4.0 m$^3$. What is the work done on the gas if it expands at constant pressure to twice its initial volume.

A certain gasoline engine has an efficiency of 30.0% What would the hot reservoir temperature be for a Carnot engine having that efficiency, if it operates with a cold reservoir temperature of $200^{\circ} \mathrm{C}?$

Heat engine $X$ takes in four times more energy by heat from the hot reservoir than heat engine $Y$. Engine $X$ delivers two times more work, and it rejects seven times more energy by heat to the cold reservoir than heat engine $Y$. Find the efficiency of (a) heat engine $X$ and (b) heat engine $Y$.

Is it possible to construct a heat engine that creates no thermal pollution? What does this tell us about environmental considerations for an industrialized society?

A 5.0-kg block of aluminum is heated from 20$^ { \circ } \mathrm { C }$ to 90$^ { \circ } \mathrm { C }$ at atmospheric pressure. Find the increase in its internal energy.

A bag contains 50 red marbles and 50 green marbles.
(a) You draw a marble at random from the bag, notice its color, return it to the bag, and repeat the process for a total of three draws. You record the result as the number of red marbles and the number of green marbles in the set of three. Construct a table listing each possible macrostate and the number of microstates within it. For example, RRG, RGR, and GRR are the three microstates constituting the macrostate 1G,2R.
(b) Construct a table for the case in which you draw five marbles instead of three.