1. Water of mass $m$ at an initial temperature of 20 oC is provided with thermal energy at a rate $P$. Its temperature rises to 30 oC in time $t$.

The rate of energy transfer is doubled and the mass of the water is halved. What is the final temperature, in time $t$, if the initial temperature is again 20 oC?

2. A chemical reaction occurs inside a solid of mass $m$ and specific heat capacity $c$. The initial temperature of the solid is $50K$.

What is the minimum energy that the reaction must release to increase the temperature of the solid to 100$°C$?

3. The albedo at the poles of Earth during a particular day is 0.8. What is the value of the absorbed intensity if the solar intensity is 700 W m^−2?

4. Which of the following real gases at atmospheric pressure would be least likely to approximate to an ideal gas?

5. Under what conditions of density and pressure does the following graph represent how the volume of a real gas varies with temperature at constant pressure?

6. 100 ml of water at 20oC is poured in an aluminum container and heated at a constant rate until all of the water is boiled. After time t1​ water starts to boil, and at time t2​ all of the water has boiled away.

Which of the following statements are correct?

• I.	If a glass container with the same mass is used instead of aluminum, t1​ increases. (cglass​)
  II.	If the container with water is thermally isolated, t2​ decreases.
  III.	If more water is added to the container, t1​ increases.

7. Container 1 contains 128g of oxygen (32g mol^−1) and Container 2 contains 56 g of nitrogen (28gmol^−1). The graph shows how the pressure $P$ inside each container varies with volume V at constant temperature ($R$ is the molar gas constant).

Which line of the table gives the temperature inside the two containers?

8. An ideal gas piston of total volume 900 cm^3 contains 600 cm^3 of air and 300 cm^3 of water at a temperature of 27°C. The system is cooled and the piston contracts at constant pressure.

What is the approximate total piston volume at the point where the water first starts to freeze?

9. Consider the circuits below that are located side by side as shown. One of these circuits includes a thermistor, which decreases in resistance as it increases in temperature.

If the switch in the circuit on the left is closed, what will happen to the brightness of the lamp over time, and why?

10. A quantity of 2000 $kg$ Carbon Dioxide (CO2​) is maintained in a container tank. The molar mass of Carbon Dioxide (CO2​) is 44 g mol^−1. Determine the correct estimate of the number of Carbon Dioxide (CO2​) molecules in the container tank.

11. Two ideal gases $A$ and $B$ of molar masses mA​>mB​ are initially at absolute temperatures TA​. The gases are mixed together. Which of the following is correct about the average random speeds vA​ and vB​ of the molecules of A and B before and after thermal equilibrium is attained?

12. Which of the following average properties of the molecules inside piston containing an ideal gas piston stay constant when the piston expands at constant temperature?

• I.  Intermolecular potential energy.
• II.  Kinetic energy.
• III.  Frequency of collisions.

13. An ideal gas is enclosed in a container of fixed volume. When the temperature of the gas is 27oC, its pressure is $p$. Calculate the pressure in the gas when it is heated to 54oC.

14. Solar radiation is incident on a planet, whose surface absorbs 65% of incident intensity. What is the albedo of the planet?

15. On a certain day, the solar intensity on the Earth's surface is 300Wm^−2. Photovoltaic cells which have an efficiency of 20% are used to convert solar energy to electrical energy. What should be the minimum area of the photovoltaic cells to produce an output of 6.0$kW$ , assuming that the incident light is normal to the surface of the panel?

16. An ideal gas is in a fixed volume container which sits on an electronic balance. More of the same gas is added to the container. Which of the following will not change?

17. An electron accelerates through a potential difference of $7kV$. How much work is done on the electron by the field?

18. An ideal gas is enclosed in a syringe. The gas has a volume of 20 mL, a temperature of 20oC, and pressure of $10kPa$. The syringe is heated to 40oC, and the volume of the gas is reduced to 5 mL.

What is the new pressure?

19. A light bulb is lit by $1kJ$ of energy being transferred to the bulb by a potential difference of $200V$. This transfer happens over a time of 2 seconds.

What is the current passing through the bulb?

20. An electric circuit is connected as shown. An electric current of $2A$ flows through the electric cell with an internal resistance $r$.

What is the value for $r$ ?

21. Which of the following energy resources is non-renewable?

22. A cell is connected to a variable resistor. The terminal potential difference (p.d.) and current through the cell are measured and plotted on the graph shown. What is the internal resistance of the cell?

23. The diagram below shows a circuit connected to a 12$V$ battery with negligible internal resistance.

What is the value of the current $I$ through the $2\Omega$ resistor?

24. A body of water loses energy at a constant rate. Assume that the specific heat capacity of ice is half the specific heat capacity of liquid water.

Which graph shows a possible variation of temperature with time?

A.			B.
C.			D.

25. A student constructed the series circuit below.

After closing the switch, which of the following is true about how the temperature of component A and current in the circuit will change with time?