3 IB Physics Topic 3 REview

Which statement about the pressure in a column of liquid is correct? 

• It acts only vertically downwards. 
• It increases if the column width increases. 
• It increases with depth in the column. 
• It is uniform throughout the column. 

An airtight container holds a fixed quantity of gas. Its pressure and volume are measured on four occasions when the temperature is 20 °C. The results are shown in the table. Which set of readings is incorrect? 

• A
• B
• C
• D

In a vacuum flask, which methods of heat transfer are prevented by the vacuum? 

• conduction only 
• convection only
  
• conduction and convection only
  
• conduction, convection, and radiation 

A substance that is originally a solid is heated strongly for some time.
At one stage, the energy given to the substance is used as latent heat of vaporisation. At this stage, what change does the energy cause? 

• It breaks the bonds holding the molecules together. Molecules escape from the liquid. 
• It breaks the bonds holding the molecules together. The solid becomes liquid. 
• It makes the molecules move faster but there is still a strong attraction between them. 
• It makes the molecules move faster and so the temperature rises. 

Tags

NGSS.MS-PS1-4

What happens when a metal bar is heated? 

• The distance between the molecules increases, making the bar longer. 
• The molecules get larger, making the bar longer. 
• The molecules vibrate more quickly, making the bar denser. 
• The speed of the molecules increases, making the bar thinner. 

Tags

NGSS.HS-PS3-2

An ice-cube has a mass of 7.50 g. The ice-cube is at 0 °C. Heat from the surroundings reaches the ice-cube at an average rate of 1.25 J / s. How long does it take for all of the ice to melt? (specific latent heat of fusion of ice = 333 J / g) 

• 35.5s 
• 55.5s 
• 2000s 
• 3120s 

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

NGSS.HS-PS3-4

An ice pack is used to cool 0.25 kg of water. The specific heat capacity of water is 4.2 kJ / (kg °C). How much thermal energy (heat) must the ice pack extract from the water to reduce the water temperature by 15 °C? 

• 0.070kJ 
• 1.1kJ 
• 16kJ 
• 250kJ 

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

The graph shows how the temperature of a liquid varies with time when energy is supplied to the liquid at a constant rate P. The gradient of the graph is K and the liquid has a specific heat capacity c.

What is the mass of the liquid?

• $\frac{P}{cK}$

• $\frac{PK}{c}$

• $\frac{Pc}{K}$

• $\frac{cK}{P}$

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

A mass m of ice at a temperature of –5 °C is changed into water at a temperature of 50 °C.

Specific heat capacity of ice = c_i

Specific heat capacity of water = c_w

Specific latent heat of fusion of ice = L

Which expression gives the energy needed for this change to occur?

• 55 m c_w + m L

• 55 m c_i + 5 m L

• 5 m c_i + 50 m c_w + m L

• 5 m c_i + 50 m c_w + 5 m L

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

A liquid is initially at its freezing point. Energy is removed at a uniform rate from the liquid until it freezes completely.

Which graph shows how the temperature T of the liquid varies with the energy Q removed from the liquid?

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