7. A well-insulated container is divided into two equal volumes by a wall. In one half there is an ideal gas and the other is a vacuum as shown below.

The wall is now removed. Which one of the following correctly gives the changes, if any, that take place in the internal energy and entropy of the gas?

	Internal energy	Entropy
	stays the same	stays the same
	stays the same	Increases
	decreases	stays the same
	decreases	Increases
	increases	Increases

(1)

8. An ideal gas is kept in a container of fixed volume at a temperature of 30 °C and a pressure of 6.0 atm. The gas is heated at constant volume to a temperature of 330°C.

The new pressure of the gas is about

	0.60 atm.
	3.0 atm.
	12 atm.
	66 atm.
	120 atm

(1)

9. The work done by an ideal gas as it expands isothermally from a state of volume V₁ to a volume V₂ is W.The work done by the gas as it expands adiabatically from the same initial state to a state of volume V₂ is

	zero.
	less than W but not zero.
	W.
	greater than W.
	unknown because of insufficient information.

(1)

10. The diagram shows the pressure / volume (p/V) diagram for one cycle PQRS of an engine.

In which sections of the cycle is work done on the engine?

	SP only
	PQ only
	SP and PQ only
	SP and PQ only
	RS and SP only

(1)

11. W hat physical property causes a meniscus in a measuring cylinder?

	Capillary Effect
	Vapor Pressure
	Surface Tension
	Entropy
	Gravitation

(1)

12. The diagram below shows plane wave fronts of a wave that is approaching the boundary between two media, X and Y. The speed of the wave is greater in medium X than in medium Y. The wave crosses the boundary.

Which of the following diagrams is correct?

	None of these graphs is correct

(1)

13. Which is true of the image of the object shown below?

	It is located behind the object and real.
	It is located between the focal point and the mirror.
	It is located on the opposite side of the mirror and is upright.
	It is located between the object and the mirror and is real.
	It is located between the object and the mirror and is virtual.

(1)

14. Two insulated gas cylinders are connected by a tube of negligible volume as shown below.

Cylinder A is full and cylinder B is empty. Which is true of this system if the tap (valve) is opened?

I. ΔU is positive

II. Entropy is 0

III. The process is adiabatic

	Only I
	Only I and II
	Only III
	Only II and III
	None of the above is correct

(1)

15. Light is incident on an air-glass boundary as shown below.

Which one of the following is a correct statement of Snell’s law?

	sin P = constant × sin R
	sin P = constant × sin S
	sin P = constant × sin Q
	sin Q = constant × sin R
	sin Q = constant × sin S

(1)

[Total: 15]

PART 2: SHORT-ANSWER QUESTION