1. 100 ml of water at 20oC is poured in an aluminum container and heated at a constant rate until all of the water is boiled. After time t1​ water starts to boil, and at time t2​ all of the water has boiled away.

Which of the following statements are correct?

• I.	If a glass container with the same mass is used instead of aluminum, t1​ increases. (cglass​<caluminum​)
  II.	If the container with water is thermally isolated, t2​ decreases.
  III.	If more water is added to the container, t1​ increases.

2. 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$°C$?

3. 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?

4. 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?

5. 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.

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

7. 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?

8. 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?

9. 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?

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

11. 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?

12. An ideal gas is enclosed in a syringe. The gas has a volume of $20mL$, a temperature of 20oC, and pressure of $10kPa$. The syringe is heated to 40oC, and the volume of the gas is reduced to $5mL$.

What is the new pressure?

13. 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?

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

15. An inflated balloon containing an ideal gas at temperature T in degrees Celsius floats in a room where the atmospheric pressure is $P$. The volume remains constant at V. If the balloon contains $M$ moles of the gas, which of the following is true?

16. 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?

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

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

19. 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?

20. A wire carries electrical current. If 9.0×10^12 electrons pass a given point in the wire every 4.5 seconds, what is the current in the wire?

21. 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?

22. 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?

23. 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?

24. 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

25. 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.