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. 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?

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

4. 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.

5. 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?

6. 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?

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

8. 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?

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

10. 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 $B$.

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. 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?

13. 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?

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

15. Electrons are accelerated between two conducting plates that have a potential difference of $100V$. Estimate the total energy that would be delivered to 10^21 electrons by the conducting plates.

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 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?

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

20. 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?

21. 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.

22. 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?

23. 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?

24. 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$°C$?

25. 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?