1. 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 $B$.

2. 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?

3. 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.

4. A spherical object of surface area $A$ and absolute temperature $T$ can be regarded as a black body. The power of the radiation emitted from the object is $P$. What would be the power of the radiation emitted by an object with an absolute temperature of $2T$ and a surface area of A/2?

5. 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?

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

7. 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?

8. 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.

9. 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?

10. 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.

11. A light dependent resistor (LDR) and a $10k\Omega$ resistor are connected in series to a $12V$ D.C supply as shown

When the LDR is in the dark it has a resistance of $20k\Omega$ . Which of the following gives the potential difference $V$ across the light dependent resistor under these conditions?

12. 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?

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. 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?

15. Which of the graphs below best describes the change in average kinetic energy of the molecules of a beaker of water as it is heated at a constant rate until it completely boils away?

A.			B.
C.			D.

16. 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?

17. A material with a mass of m is heated. The graph shows the variation of the temperature of the material with the energy supplied.

Which one of the following gives the specific heat capacity of the material?

18. Which of the following is a non-renewable energy resource?

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. 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. 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?

22. 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?

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. 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?

25. 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?