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 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?

3. 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?

4. 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?

5. 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?

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

7. 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?

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

9. 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?

10. 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?

11. 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?

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

13. 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.

14. 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?

15. 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?

16. If the current in the circuit below is 0.5 A, what is the potential difference $V$?

17. 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?

18. 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.

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

20. 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?

21. 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?

22. 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?

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

24. 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?

25. 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?