1. Water in a beaker is heated on a hot plate at a rate $P$. The graph shows the change in temperature of the water over time.

Which graph correctly shows the new change in temperature of the water when the rate of thermal energy transfer is increased?

The original graph is shown by the dotted line.

A.			B.
C.			D.

2. Which of the following pairs constitutes a renewable and non-renewable source of energy?

3. 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?

4. A student is using the equation $pV=nRT$ to solve for $n$ with the following percentage uncertainties in the measurements.

What is the percentage uncertainty in the calculated value of n?

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

6. Several energy conversions occur in power stations. Examples of electricity generation that both involve energy transfer from thermal to electrical are

7. An area on the Earth's surface receives an average solar intensity of 250 Wm^−2. What is the minimum area of photovoltaic cells needed to generate 2 kW of electrical power if the photocells operate at 40% efficiency?

8. The following three statements give possible reasons why the average intensity of sunlight incident on a solar panel during a day on earth is only a fraction of the solar constant.

• I.	Scattering of sunlight in the atmosphere
  II.	Rotation of the earth
  III.	The surface of the solar panel is not perpendicular to incident of sunlight

Which of the statements are correct?

9. The variation of terminal potential difference $V$ across an electric cell with current $I$ coming out of the cell is shown in the graph.

What are the values of the emf $ϵ$ and internal resistance $r$ of the electric cell used in this circuit?

10. Systems A and B both consist of an ideal gas at initial temperature $T$. In System A, the temperature of the gas is increased. In System B, gas molecules are added with the temperature of the system remaining constant.

Which of these statements about the total intermolecular potential energy of the two systems is correct?

11. Gas System A contains non-interacting molecules of negligible size at pressure P, whilst Gas Systems B and C contain large, strongly interacting molecules at pressures $10P$ and P/2​, respectively.

Which line of the table correctly describes how closely the three systems resemble an ideal gas?

12. 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.

13. 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?

14. 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?

15. 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?

16. An ideal gas is held in a container of volume $V$ and at pressure $P$. Gas is pumped into the container so that the number of molecules doubles and heat is added so that the average kinetic energy of the gas also doubles. The volume is adjusted so that the pressure remains constant. What is the new volume of the container?

17. 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?

18. A circuit of a cell of electromotive force (emf) $18.0V$ and negligible internal resistance connected to three resistors of resistance $6.0\Omega$

The ammeter is ideal. What is the reading of the ammeter?

19. The average radius of Neptune's orbit around the Sun is approximately 30 times the orbital radius of earth. Estimate the solar constant of Neptune.

20. 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?

21. 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.

22. 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 $r$ ?

23. 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?

24. Two solid substances of equal mass are heated with the same power input. The graph below shows how the temperatures of the substances vary with time during heating.

Which of the following statements are correct?

• I.	Substance $A$ has a lower specific heat capacity than Substance $B$ when they are in the same physical state.
  II.	The specific heat capacity of each substance is lower in the solid state than the liquid state.
  III.	Substance $A$ has a lower specific latent heat of fusion than Substance $B$.

25. The following graph shows the relationship between current and potential difference across an unknown component in a series circuit.

Which of the following is true about the component?