1. An immersion heater of constant power output is used to supply thermal energy to a cup of water at 373 $K$. The heater is turned on at time $t=0$. Which graph shows a possible variation of temperature $T$ of the water, with time t?

A.			B.
C.			D.

2. 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?

3. 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?

4. 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 $B$.

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

6. 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$°C$?

7. 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 $r$ ?

8. If the radius of a segment of wire is doubled, and its length decreases by half, by what factor does the wire's resistance change?

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 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?

11. 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?

12. 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?

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

14. 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?

15. 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?

16. 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.

17. A circuit is connected across a $12V$ battery which provides $60J$ of electrical energy per second.

What is the rate of charge flow across the conductor?

18. A cylinder of fixed volume contains $n$ moles of an ideal gas at constant temperature. An additional $n$ moles of the same gas is forced into the cylinder via a one-way valve without changing the temperature. Which of the following best explains the final pressure in the cylinder?

19. 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?

20. 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.

21. 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?

22. 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?

23. 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?

24. 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.

25. 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?