PHY1506 EXAM
PACK 2023
QUESTIONS WITH
ANSWERS
,INSTRUCTIONS:
• This paper consists of 5 pages.
• The paper consists of 6 questions for a total of 100 marks.
• Marks for each question or part are indicated in brackets on the right of the question.
• Show all the necessary steps in carrying out your calculations.
• The information given on page 4 maybe used without proof.
• Answer ALL questions.
[TURN OVER]
, PHY1506
May/June 2017
Question 1
4 3
The figure below represents a pV [p in Pa and
× 10
V in m] diagram for 7.50 moles of an ideal diatomic
gas taken through the cycle a → b → c.
(a) Calculate the highest temperature reached by the gas during the cycle (4)
(b) What net work does the gas do during the cycle? (4)
(c) How much heat is exchanged with the gas during part bc of the cycle? Does it enter or
leave the gas? (4)
(d) What is the change in the internal (thermal) energy of the gas during part bc of the(4)
cycle?
(e) What is the change in the internal (thermal) energy of the gas during the entire cycle?
(4)
[20]
Question 2
(a) The figure below shows three electric charges labeled
1,Q2,Q3Q
, and some electric field lines in the
region surrounding the charges.
What are the signs of the three charges? (6)
[TURN OVER]
Page 2 of 5
, PHY1506
May/June 2017
◦ ◦
(b) A 400-g piece of metal
at 120.0 C is dropped into a cup containing 450 g of water at C.15.0
The
◦
final temperature of the system is measured to be C. 40.0
Calculate the specific heat of the metal,
assuming no heat is exchanged with the surroundings or theThe cup.specific heat of
water is
4186 J/(kg.K). (6)
(c) Why doing a change of phase, heat is absorbed but the temperature does not rise?(3)
[15]
Question 3
(a) Two positive point charges +4.00 µC and +2.00µC are placed at the opposite corners of a rectang
as shown in the figure.
What are the potentials at points A and B (relative to infinity) due to these
charges? (10)
(b) A heat engine with an efficiency of 30.0% performs 2500 J How
of work.
much heat is discharged to
the lower temperature reservoir? (10)
[20]
Question 4
(a) The magnetic field of a moving charge is given by
~ = µ0 qv sin θ
B .
4π r 2
(i) Which law does this equation represent? (2)
(ii) What do r,µ,v and θ represent? (4)
(b) What is an electromagnetic induction? (3)
(c) State Faraday’s law (6)
[15]
[TURN OVER]
Page 3 of 5
PACK 2023
QUESTIONS WITH
ANSWERS
,INSTRUCTIONS:
• This paper consists of 5 pages.
• The paper consists of 6 questions for a total of 100 marks.
• Marks for each question or part are indicated in brackets on the right of the question.
• Show all the necessary steps in carrying out your calculations.
• The information given on page 4 maybe used without proof.
• Answer ALL questions.
[TURN OVER]
, PHY1506
May/June 2017
Question 1
4 3
The figure below represents a pV [p in Pa and
× 10
V in m] diagram for 7.50 moles of an ideal diatomic
gas taken through the cycle a → b → c.
(a) Calculate the highest temperature reached by the gas during the cycle (4)
(b) What net work does the gas do during the cycle? (4)
(c) How much heat is exchanged with the gas during part bc of the cycle? Does it enter or
leave the gas? (4)
(d) What is the change in the internal (thermal) energy of the gas during part bc of the(4)
cycle?
(e) What is the change in the internal (thermal) energy of the gas during the entire cycle?
(4)
[20]
Question 2
(a) The figure below shows three electric charges labeled
1,Q2,Q3Q
, and some electric field lines in the
region surrounding the charges.
What are the signs of the three charges? (6)
[TURN OVER]
Page 2 of 5
, PHY1506
May/June 2017
◦ ◦
(b) A 400-g piece of metal
at 120.0 C is dropped into a cup containing 450 g of water at C.15.0
The
◦
final temperature of the system is measured to be C. 40.0
Calculate the specific heat of the metal,
assuming no heat is exchanged with the surroundings or theThe cup.specific heat of
water is
4186 J/(kg.K). (6)
(c) Why doing a change of phase, heat is absorbed but the temperature does not rise?(3)
[15]
Question 3
(a) Two positive point charges +4.00 µC and +2.00µC are placed at the opposite corners of a rectang
as shown in the figure.
What are the potentials at points A and B (relative to infinity) due to these
charges? (10)
(b) A heat engine with an efficiency of 30.0% performs 2500 J How
of work.
much heat is discharged to
the lower temperature reservoir? (10)
[20]
Question 4
(a) The magnetic field of a moving charge is given by
~ = µ0 qv sin θ
B .
4π r 2
(i) Which law does this equation represent? (2)
(ii) What do r,µ,v and θ represent? (4)
(b) What is an electromagnetic induction? (3)
(c) State Faraday’s law (6)
[15]
[TURN OVER]
Page 3 of 5
