".~/) -/ . . L-2/T-1IME Date: 30/0112012 'BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY, DHAKA L-2/T-l B. Sc. Engineering Examinations 2010-2011 Sub: EEE 259 (Electrical and Electronic Technology) Full Marks: 280 Time: 3 Hours USE SEPARATE SCRIPTS FOR EACH SECTION -_._--_ ....~----_ ..... _-_._ ... _--- ..._-_._--_ .._ _-_ __ ..__ ._- SECTION-A There are FOUR questions in this section. Answer any THREE. The figures in the margin indicate full marks. . 1. (a) How does the voltage buildup in a shunt DC generator during starting? What could cause voltage buildup failure on starting? How can these problems be remedied? Explain briefly with appropriate diagrams. (20) (b) What types of losses are present in a real DC machine? Draw the power flow diagram for DC machines. (11 %) (c) The magnetization curve for a shunt DC generator is given in Figure for Q. l(c). Following informations are given: RA = 0.5 n, RF = 57.5 n, Radj = 0- 100 n. Determine: (i) the critical resistance. (ii) the value of Radjto produce an internal voltage of 270 V. (iii) the value of internally generated voltage when Radj = 100 n. (15) 2. (a) Derive the torque-speed characteristics of shunt and series DC motors and compare between them. (14 %) (b) Explain briefly Ward-Leonard speed control system for dc motors. What are the advantages and disadvantages of this system? (20) (c) A 20 hp, 220 V, 1500 r.p.m. DC shunt motor with compensating winding has an armature resistance of 0.01 n. It's no-load speed is 1500 r.p.m. The field circuit is composed' of an internal resistance.of 20 n and an adjustable resistance which can be varied between 0- 150 n. There are 1000 turns per pole on the field windings. Calculate (assuming no armature reaction) speed of the motor when input current is 75 A, 125 A and 175 A. (Assume Radj = 75 n). (12) 3. (a) Draw the exact equivalent circuit of a transformer. From this obtain the approximate equivalent circuit by making reasonable assumptions. (11 %) (b) Describe briefly the open circuit and short circuit tests of a transformer with necessary diagrams. Discuss how different parameters of the equivalent circuit can be obtained from these tests. (20) (c) For the circuit shown in Fig. for Q. 3(c) calculate the value of E out and I p . (Assume frequency = 60 Hz). :2. > (15) Contd P12
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".~/)-/
. .
L-2/T-1IME Date: 30/0112012'BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY, DHAKA
L-2/T-l B. Sc. Engineering Examinations 2010-2011
Sub: EEE 259 (Electrical and Electronic Technology)
Full Marks: 280 Time: 3 Hours
USE SEPARATE SCRIPTS FOR EACH SECTION-_._--_ ....~----_....._-_._ ..._--- ..._-_._--_ .._ _-_ __ ..__._-
SECTION-A
There are FOUR questions in this section. Answer any THREE.
The figures in the margin indicate full marks.
. 1. (a) How does the voltage buildup in a shunt DC generator during starting? What could
cause voltage buildup failure on starting? How can these problems be remedied? Explain
briefly with appropriate diagrams. (20)(b) What types of losses are present in a real DC machine? Draw the power flow diagram
for DC machines. (11%)(c) The magnetization curve for a shunt DC generator is given in Figure for Q. l(c).
Following informations are given: RA = 0.5 n, RF = 57.5 n, Radj = 0 - 100 n.Determine:
(i) the critical resistance.
(ii) the value of Radjto produce an internal voltage of 270 V.
(iii) the value of internally generated voltage when Radj= 100 n.
(15)
2. (a) Derive the torque-speed characteristics of shunt and series DC motors and compare
between them. (14 %)(b) Explain briefly Ward-Leonard speed control system for dc motors. What are the
advantages and disadvantages of this system? (20)(c) A 20 hp, 220 V, 1500 r.p.m. DC shunt motor with compensating winding has an
armature resistance of 0.01 n. It's no-load speed is 1500 r.p.m. The field circuit is
composed' of an internal resistance.of 20 n and an adjustable resistance which can be
varied between 0 - 150 n. There are 1000 turns per pole on the field windings. Calculate
(assuming no armature reaction) speed of the motor when input current is 75 A, 125 A
and 175 A. (Assume Radj= 75 n). (12)
3. (a) Draw the exact equivalent circuit of a transformer. From this obtain the approximate
equivalent circuit by making reasonable assumptions. (11 %)(b) Describe briefly the open circuit and short circuit tests of a transformer with necessary
diagrams. Discuss how different parameters of the equivalent circuit can be obtained
from these tests. (20)
(c) For the circuit shown in Fig. for Q. 3(c) calculate the value of Eout and Ip. (Assume
frequency = 60 Hz). :2. > (15)Contd P12
=2=
EEE259 (ME)
4. (a) Prove that a set of balanced three-phase currents can produce a rotating magnetic field.
(b) Draw the equivalent circuits of synchronous motor and generator.
(c) A 220 V, 60 Hz, 8 pole Y connected induction motor has following parameters:
Rl = 0.15 n, R2 = 0.2 n, Xl = 0.45 n, X2 = 0.45 n XM = 29.8 nFor a slip of2.8% at the rated voltage and frequency, find the motor's
(i) Starting torque
(ii) Speed
(iii) Power factor
(iv) Converted and output power
(v) induced torque,
(vi) load torque
(vii) efficiency
Given that rotational losses are 940 Wand are assumed to be constant. The core loss is
lumped in with the rotational loss.
SECTION -B
There are FOUR questions in this section. Answer any THREE.
The questions are of equal value.
5. (a) Describe diode equivalent circuits models.
(b) Draw input and output waveform of bridge rectifier in a same plot. (Consider
practical diodes). Also prove for a bridge rectifier, the ripple factor is 1.21. (Consider
Ideal diodes).
(c) Assuming the diodes to be ideal, find the values of I and V in the circuits. Consider
constant voltage drop model diode.
(11%)(10)
(25)
- 10" ill/1i7T
Contd P/3
•
=3=
EEE 259 (ME}
6. (a) Considering constant voltage drop model diode, draw output waveform for the
L-2/T-l/ME Date: 22/02/2012BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY, DHAKA
L-2/T-l B. Sc. Engineering Examinations 2010-2011
Sub: ME 201 (Basic Thermodynamics)
Full Marks: 280 Time: 3 Hours
The figures in the margin indicate full marks.
USE SEPARATE SCRIPTS FOR EACH SECTION
SECTION-A
There are FOUR questions in this Section. Answer any THREE.P-h chart (R-13 4a) supplied. Steam Table (SI) supplied.
Assume reasonable data if necessary
1. (a) Deduce an expression of air standard thermal efficiency of a Diesel cycle engine, in
terms of compression ratio and cut-off ratio. (16 %)(b) What is the limitation of using higher compression ratio in Otto cycle engines?
Briefly explain. (15)(c) An air standard cycle operates with a compreSSIOn ratio of 16 and maXImum
temperature of 1500 °C. Air at the beginning of compression stroke is at 25°C and 1 bar
pressure. Calculate the following (15)(i) Cut-off ratio (ii) Cycle efficiency (iii) MEP.
2. (a) Briefly explain the working principle of a Turbo-Jet engine. How is the performance
of a jet engine is expressed?
(b) Define pressure ratio. Briefly discuss the effect pressure ratio on the performance of
Brayton cycle gas turbine, in relation to efficiency and net work.
(c) A simple Brayton cycle operates with a maximum and minimum temperature of 1000
°C and 30°C respectively. The pressure ratio is 6 and the isentropic efficiency of the
compressor is 85% and that of the turbine is 90%. Calculate the actual cycle efficiency.
(16 %)
(16)
(14)
(10)
(8)
(12)
3. (a) Briefly explain the role of the regenerator on the performance ofa Stirling cycle.
(b) Write a short note on "Thermo-Electric Refrigeration".
(c) Define "Equivalence Ratio". State the reasons why rich or lean air-fuel mixtures are
needed for combustion in engines.
(d) The dry volume basis analysis of natural gas in a burner shows 10% CO2, 0.5% CO,
2.5% O2 and 87% N2. Calculate the mass basis AF ratio and Equivalence ratio. Comment
on the amount of air used. (16%)
4. (a) Briefly explain "Sub-coding" and "Superheting" In a vapour compression
refrigeration cycle. (8)(b) Draw a schematic diagram of an NH3-Water vapour absorption refrigeration system
identifying the compounds. (12)Contd P12
=2=ME 201Contd ... Q. NO.4
(c) When an air conditioner is operated in summer, lots of water needs to be drained out
from it. Briefly explain this situation in relation to psychometry.
(d) An ideal vapour compression cycle using R-134a operates with an evaporator
temperature of -10°C and condenser temperature of 40°C. If the cooling capacity of the
system is 4 TR, calculate -
(i) Mass flow rate of the refrigerant
(ii) Power required to drive the compressor
(iii) COP and EER of the system.
SECTION -B
There are FOUR questions in this Section. Answer any THREE.Assume reasonable values for missing data, if any. Necessary charts are attached.
(10%)
(16)
5. (a) State the Kelvin - Planck and Clausius statements of the Second Law of
Thermodynamics and show their equivalence with an example. (26%)(b) What do you understand by 'Perpetual Motion Machine of the First and Second
kind'? (12)(c) It is known that the temperature of air rises as it is compressed. An inventor thought
about using this high-temperature air to heat buildings. He used a compressor driven by
an electric motor. The inventor claims that the compressed hot-air system is 25% more
efficient than a resistance heating system that provides an equivalent amount of heating.
Is this claim valid? Or is this an perpetual motion machine? explain. (8)
6. (a) Explain First Law of Thermodynamics as an energy conservation principle. (10)(b) Give the energy balance formula for commonly used steady flow devices. Give an
example ofIsoenthalpic Steady-flow device. (16)(c) Air at 600 kPa and 500 K enters an adiabatic nozzle that has an inlet-to-exit area ratio
of2:1. The inlet air velocity is 120 mls and leaves with a velocity of380 mls. Determinethe exit air temperature and exit pressure of the air. The relationship between properties
of air can be found from the table below: (20%)T(k) h (KJ/kg) u (KH/kg)400 400.98 286.16450 451.80 322.62500 503.02 359.49550 555.74 396.86
7. (a) Draw the pressure -vs. Volume diagram for pure substances that - (i) expand on
freezing and (ii) Contract on freezing. Show different phases on the diagrams. (14)
Contd P/3
..
..=3=
ME 201Contd ... Q. NO.7
(b) What do you understand by 'Triple Point' and 'Sublimation'? How can these be used
to serve practical purpose? (10)(c) Derive the expression of work done for a polytropic process. What happens to the
workdone expression when the process is isothermal? (16)(d) A friction less piston-cylinder device contains 2 Kg of nitrogen at 100 kPa and 300 K.
Nitrogen is now compressed slowly according to the relation pyl.4 = Constant until it
reaches a final temperature of 360 K. Calculate the work input during this process.
Assume the process to be Quasi - Equilibrium. Also take nitrogen as an ideal gas.
8. (a) How does Rankine Cycle eliminate various limitations of Camot cycle? How does it
improve the efficiency?
(b) What do you know about Superheating?
(c) Consider a regenerative cycle using steam as the working fluid steam leaves the boiler
and enter the turbine at 4 MPa, 400°C. After expansion to 400 kPa, some of the steam is
extracted from the turbine to heat the feedwater in an open feedwater heater. The pressure
in the feedwater heater is 400 kPa, and the water leaving it is saturated liquid at 400 kPa.
The steam not extracted expands to 10 kPa. Determine the cycle efficiency.
(c) What is 'Binary Yapour Power cycle'?
(25)
€)
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~ 0.4::tiltil
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j
Prepared by CENTER FOR APPLIED THERMODYNAMIC STUDIES. University of IdahoCOPYRIGHT 1992 AMERICAN SOCIETY OF HEATING. REFERlGERATING AND
AIR-CONDITIONING ENGINEERS
Enthalpy (kI/kg)
~IIFIGURE Bl Pressure-enthalpy diagram for refrigerant R134a.
0.150 111.37 0.001 053 I. I 593 466.94 2052.7 2519.7 '167.1 J 2226.5 2693.6 1.4336 5.7897 7.2233Telllp. v h s u 0.175 J 16.06 0.001 057 1.0036 186.80 2038.1 2524.9 486.99 22136 2700.6 1.4849 5.6868 7.17179 °C m3/kg kJ/kg kJ/kg K kJ/kg 0.200 120.23 0.001 061 0.8857 504.49 2025.0 2529.5 501.70 2201.9 2706.7 1.5301 5.5970 7.1271PACt: 1/~~ 0.225 124.00 0.001 064 0.7933 520.47 2013. I 2533.6 520.72 2 I91.3 2712.1 1.5706 5.5173 7.0878
)0'
..,0 ,'-;., , @).
OUReE;. Reproduced from Joseph H, Keenan. Frederick G. Keyes. Philip .G. Hill, and Joan G. Moore, Steam TilhI,'s (New York: John 'Vile)' &:.OIlS. Inc .. 1969) wilh permission.
BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY, DHAKA
L-2/T-1 B. Sc. Engineering Examinations 2010-2011
Sub: ME 241 (Engineering Mechanics)
Full Marks: 280 Time: 3 Hours
The figures in the margin indicate full marks.
USE SEPARATE SCRIPTS FOR EACH SECTION
SECTION -A
There are FOUR questions in this Section. Answer any THREE.
Symbols indicate their usual meaning.
1. (a) A 40 kg cylinder is supported by three wires as shown in figure for Q. No. 1(a).
Determine the tension in each-wire. Use vector method. (237j )
(b) A force of magnitude 300 N acts at the point A in a plane parallel to x-y as shown in
the figure for Q. No. l(b). Replace this 300 N force by an equivalent force-couple
system at O. Use vector method.
\I
I
\-
/z
x.
Contd P12
(23)
I','
=2=
ME 241
2. (a) A frame is shown in the figure forQ. No. 2(a). Determine the force in the member
CD when P = 1.5 kN and t/J = 30°. Also determine reactions at A and B. (23 %)~-~-"- - =-"~,-="_._-,--=,-=-"._="=~,._-=-,,=-=, =.._._=., .. _-=----=-".,.=.__._-=._,.-=..... ~, ---- ••• _e ••• _-.,
B
5m
(b) Using section method determine the forces in the members DG and DF of the truss
as shown in Fig. for Q. No. 2(b). State whether the members are in tension or
3. (a) A glass rod AB as shown in figure for Q. No. 3(a), weighs 0.142 kg and is 150 mm
long. It is placed in a glass tumbler C in a position of equilibrium. If the tumbler is 63
mm diameter and if all surfaces are smooth, what is the angle e?_....._"----~'..,""--.----=-=.
A
c
(23)
(23%)
(b) A uniform ladder of mass 12 kg, rests against a wall and a horizontal surface as
shown in Fig. for Q. No. 3(b). If the coefficient of friction at A and B is 0.3, find the
smallest force that will prevent motion of the ladder to the left at A. (23)
Contd P/3
"
' ..
=4=
ME 241Contd ... Q. No.5
(b) The 10-kg block B is supported by the 40-kg block A which is pulled up an incline
by a constant 500 N force as shown in Figure for Q. 5(b). Neglecting friction between
the block and the incline and knowing that block B does not slip on block A, determine
the smallest allowable value of the coefficient of static friction between the blocks. (20)
6. (a) Block A moves down with a constant velocity of 1 m/s as shown in Figure for
Q. 6(a). Determine (i) the velocity of block C, (ii) the relative velocity of portion D of
the cable with respect to block A. (20)
--Eigure forQ. 6(a)
(b) As shown in Figure for Q. 6(b) a thin circular rod is supported in a vertical plane by
a bracket at A. A sprint is attached to the bracket and loosely wound around the rod of
constant k = 40 Nlm and undeformed length equal to the arc of circle AB. A 200-g collar
C, is not attached to the spring, can slide without friction along the rod. Knowing that
the collar is released from rest at an angle () with respect to the vertical, determine
(i) the smallest value of () for which the collar will pass through D and reach point A,
(ii) the velocity of the collar as it reaches point A.
Contd .... : ..... PIS
(26%)
- . ~i'"
••
=4=
ME 241Contd eo. Q. No.5
(b) The 10-kg block B is supported by the 40-kg block A which is pulled up an incline
by a constant 500 N force as shown in Figure for Q. 5(b). Neglecting friction between
the block and the incline and knowing that block B does not slip on block A, determine
the smallest allowable value of the coefficient of static friction between the blocks. (20)
6. (a) Block A moves down with a constant velocity of 1 m1s as shown in Figure for
Q. 6(a). Determine (i) the velocity of block C, (ii) the relative velocity of portion D of
the cable with respect to block A. (20)
-figure forQ. 6(a)
(b) As shown in Figure for Q. 6(b) a thin circular rod is supported in a vertical plane by
a bracket at A. A sprint is attached to the bracket and loosely wound around the rod of
constant k = 40 Nlm and undeformed length equal to the arc of circle AB. A 200-g collar
C, is not attached to the spring, can slide without friction along the rod. Knowing that
the collar is released from rest at an angle e with respect to the vertical, determine
(i) the smallest value of e for which the collar will pass through D and reach point A,
(ii) the velocity of the collar as it reaches point A.
~_-=F-=-i,glirefor Q. 6(b)
Contd PIS
(26%)
),,::-
....
=5=
ME 241
7. (a) Collars A and B are pin-connected to bar ABD and can slide along fixed rods as
shown in Figure for Q. 7(a). Knowing that at the instant shown the velocity of A is 0.9
m/s to the right, determine (i) the angular velocity of ABD, (ii) the velocity of point D. (20)
(b) A cord is wrapped around the inner drum of a wheel and pulled horizontally with a
force of 200 N as shown in Figure for Q. 7(b). The wheel has a mass of 50 kg and a
radius of gyration of 70 mm. Knowing that JLs = 0.20 and JLk = 0.15, determine the"\
acceleration of G and the angular acceleration of the wheel. (267j )
1000101 OOmm
200N
(20)
,/
1J. ,
1,II .
Figure for Q. 7(b)
(a) A uniform rod of length Land mass m is supported as shown in Figure for Q. 8(a)
with b = 0.2 L, when the cable attached to end B suddenly breaks. Determine at this
instant (i) the acceleration of end B, (ii) the reaction at the pin support. r--1
I1- '--- - ------1ii
8.
~ F--"igurefor Q~(~) _.~-~(b) Knowing that at the instant as shown in Figure for Q. 8(b) the angular velocity of rod
AB is 15 rad/s clockwise, determine (i) the angular velocity of rod BD, (ii) the velocity
of the midpoint of rod BD. (267j )~.---.---'----------
Figure for Q. 8(b)
L-2/T-l/ME Date: 07/03/2012BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY, DHAKA
L-2/T-I B. Sc. Engineering Examinations 2010-2011
Sub: MATH 261 (Vector Calculus, Matrices, Laplace Transforms and Series Solutions)
Full Marks: 280 Time: 3 HoursThe figures in the margin indicate full marks.Symbols used have their usual meanings.
USE SEPARATE SCRIPTS FOR EACH SECTION
SECTION -AThere are FOUR questions in this Section. Answer any THREE.
1. (a) Define the following with examples: ~ (16 %)(i) Upper Triangular Matrix (ii) Symmetric Matrix,(iii) Skew-Symmetric Matrix (iv) Trace of a Matrix,
(b) Are the following vectors linearly dependent? If so, express each of the following
vector as a linear combination of the other two. (15)Yl = (0,3, 1, -1), Y2= (6, 0, 5, 1), Y3 = (4, -7, 1,3).
(c) Determine the values of A so that the following system of linear equations
x + y + AZ = 1
x + AY+ z= A
AX + y + Z = A2
has (i) Unique solution (ii) No solution (iii) Infinitely many solutions.
2. (a) Find the eigenvalues and the corresponding eigenvectors of the matrix
A ~ l: ~;]Also find the eigenvalues of AlO and the corresponding eigenvectors.
(b) Reduce the quadratic form
q = 6xf + 3xi + 3xj - 4xlx2 - 2x2x3 + 4x3xl
to the sum of squares and find the corresponding linear transmissions. Also find its rank,index and signature.
3. (a) Find the curl ofthe gradient of <po
(b) If y = WXI, prove that w = ~ curl y, where w is a constant vector.
(c) State Green's theorem in the plane. Verify the theorem in the plane for
c
around the boundary of the region defined by y2 = 8x and x = 2.
Contd P/2
(15)
(23%)
(23)
(10)
(10)
(26%)
=2=
MATH 261
4. (a) Is E = (x3z - 2xyz)i +(xy - 3x2yz)j + (yz2 - xz)k solenoidal? If so, find vector V such
thatE = "V x V. (20)(b) State Stoke's theorem. Evaluate ffi1xF.nds for E = (2x -y)i _yz2 j - y2zk, where S
s
is the upper half surface of the sphere x2 + y2 + Z2= 1 and C is its boundary. (16 %)(c) Find the directional derivative ofP = 4e2x-y+z at the point (1, 1, - 1) in the direction
toward the point (-3,5,6). (10)
SECTION -BThere are FOUR questions in this Section. Answer any THREE.
Symbols have their usual meaning
5. (a) Find the series solution of the differential equation (x - x2)y" + (1 - 5x)y' - 4y = 0 by
the method of Fr6benius.
(b) Show that Jz(x) = J~(x) - X-I J~(x).
6. (a) Show that (i) xJ~(x) = x In+1 (x) -nJn(x).
(ii) x2J~(x) = (n2 - n - x2) In(x )+xJn+I (x).1
(iii) fPm(x )Pn(x)dx = 0, (m * n)-1
7. (a) Prove that legendre Polynomial Pn(x) is the coefficient of hn in the expansion of
-}i(1- 2xh + h2) 2
(b) Express 2x4 + 3x3 - x2 + 7x + 1 as a legendre polynomial.
(c) State and prove Heaviside's expansion formula and using this formula find
BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY, DHAKA
L-2/T-1 B. Sc. Engineering Examinations 2010-2011
Sub :HUM 303 (Principles of Accounting)
Full Marks: 210 Time : 3 Hours
The figures in the margin indicate full marks.
USE SEPARA TE SCRIPTS FOR EACH SECTION
SECTION -A
There are FOUR questions in this Section. Answer any THREE.
1. Mr. X with available fund of Tk. 8 million is evaluating his investment opportunities.
Two projects are now available for him with different amounts of return. Both the
projects required Tk. 8 million of investments which will provide him return for next
seven years from Project Deluxe and next 5 years from Project Supreme. The details
about the return from the projects are given below:
(Amounts are in million)
Year Project Deluxe Project Supreme
1 Tk. 1.2 Tk. 2.3
2 1.4 2.3
3 1.6 2.3
4 1.8 2.3
5 2.0 2.3
6 2.2 -
7 2.4 -
Mr. X is asking for your help in evaluating the projects and making the right decision.
As an expert, recommend Mr. X which project should he undertake under the following
evaluation techniques:
(i) Payback period method
(ii) Net present value method
(iii) Internal rate of return method
(iv) Among these three methods which one do you consider as best.
(Consider the discounting rate is 12% for your analysis).
2. (a) In what situation, absorption costing will result higher net income than variable
costing? Why?
Contd P/2
(35)
(5)
=2=
HUM 303Contd ... Q. NO.3
(b) For the income year ended on December 31, 2010; you have been gIVen the
information below: (30)
Particulars
Selling price per unit
Manufacturing costs:
Direct Material cost per unit
Direct labour cost per unit
Variable manufacturing cost per unit
Fixed manufacturing cost for the period
Selling and Administrative costs:
Variable cost per unit
Fixed cost for the period
Amount (Tk)
50
8
7
5
100,000
2
80,000
During the year, a total of 10,000 units produced but only 8500 units sold.
Requirements:
(i) Determine the unit product cost under absorption costing and variable costing
techniques.
(ii) Prepare income statement under both of the techniques.
(iii) Reconcile the amount of net income under these two techniques.
3. Crown creative inc. makes high quality Personal Digital Assistant (PDA). Sales and
production data relating to the most recent year are given below: (35)
Sales (in unit) 2800
Selling price per unit (Tk.) 265
Contribution margin ratio 60%
Annual Fixed costs (Tk.) 111,300
Management is anxious to improve the company's profit performance and has asked for
several items of information.
Requirements:
(a) Compute break-even-point in units and sales Taka.
(b) Assume that sales increases by Tk. 60,000 next year. If cost behaviour patterns
remain unchanged, by how much will the company's net income increase?
(c) Refer to the original data. Assume that next year management wants to earn a Tk.
182,850 profit. How many units will have to be sold to meet this target profit?
Contd P/3
=3=HUM 303Contd no Q. NO.3
(d) Refer to the original data. The sales manager is convinced that a 15% reduction in
the selling price combined with a Tk. 56,100 increase in advertising expenditure
would cause arumal sales in units to increase by 40%. Would you recommend that
the company should do as the sales manager suggests?
(e) Refer to the original data. Compute margin of safety both in Taka and percentage
form.
(f) (i) Compute degree of operating leverage at the present level of sales.
(ii) Assume that the company like to increase its net profit by 90% next year. By
what percentage would you expect sales to increase? Use DOL to answer.
(iii) Verify your answer to (ii) by preparing income statement.
4. (a) Classify costs in terms of behaviour. (6)(b) What is the most easiest method available to separate mixed costs into fixed and
variable? What is the major disadvantage of this method? (4)(c) The data below have been taken from the cost records of Beverly Hospital. A careful
study by the company's cost analyst has determined that if the number of X-rays taken is
7000, the average operating cost is TIc 4.14 per X-ray. If the number of X-rays taken is
3000, the average operating cost is Tk. 5.65 per X-ray. (20)Requirements:
(i) Using the high and low point method, determine the variable cost per X-ray and the
fixed cost in total.
(ii) Express the variable cost and fixed cost in the form Y = a + bx.(iii) If the number of X-rays taken in a month is 4600, what total operating X-rays cost
would you expect?
(d) Suppose that you are a furniture manufacturer. You rpoduce high quality luxurious
furniture from solid wood that is supplied by a local supplier. Your manufacturing
cost is composed of three types of costs- direct material costs, direct labour costs
and manufacturing overhead cost. Name different types of cost for your company. (5)
SECTION -B
There are FOUR questions in this Section. Answer any THREE.
5. Sharif and Associates was formed on May 1, 2011 by Mr. Omar Sharif. The following
transactions took place during the first month of the operation: (35)May 1: Mr. Sharif invested Tk. 50,000 cash in the business.
May 5: Hired two employees to work in the warehouse. Both of them will be paid
a total salary ofTk. 3,000 per month.
Contd P/4
=4=
HUM 303Contd ... Q. NO.5
May 11: Purchase furniture costing Tk. 30,000. A cash payment of Tk. 10,000 was
made immediately; the reminder will be paid in six months.
May 13: Purchase office supplies for Tk. 500 on account.
May 18: Services provided to customers worth Tk. 20,000 of which Tk. 8,000 cash
received and Tk. 12,000 on account.
May 21: Paid Tk. 400 to suppliers for accounts payable due.
May 25: Received Tk. 3,000 from customers.
May 27: Withdrew Tk. 200 for personal use.
May 31: Paid monthly salary Tk. 3,000.
Requirements:
(a) Journalize the above transactions.
(b) Prepare ledger for the following two accounts-
(i) Cash account (ii) Accounts Payable account.
6. Starline Company is owned by Mr. Star. The company prepare financial statements in
every three months. The trial balance at the end of first quarter is given below:
Dr. Cr.
Cash Tk. 5,000
Prepaid Insurance 6,000
Office Equipment 60,000
Accumulated Depreciation-Equipment Tk. 9,000
Accounts Payable 2,500
Unearned Service Revenue 6,400
Mortgage payable 30,000
Capital-Mr. Star 10,000
Service Revenue 15,100
Rental Income 7,000
Salaries Expenses 9,000
Tk. 80,000 Tk. 80,000
Other data:
(i) Prepaid insurance relates to premium paid on January 1 for one year.
(ii) The mortgage interest rate is 12% per annum. (Mortgage was taken out on
February 1,2011).
Contd P/5
(35)
=5=
HUM 303Contd ... Q. NO.6
(iii) Half of the unearned service revenue has been earned by March 31, 2011.
(iv) Office equipment is being depreciated Tk. 500 per month.
(v) Salaries accrued but not paid Tk. 1700 by March 31, 2011.
(vi) Rental income earned but not received Tk. 2,500.
Requirements:
(a) Prepare the adjusting entries on March 31,2011.
(b) Complete the ten column worksheet for the quarter.
7. The Mound view Motel opened for business on May 1, 2011. Its trial balance before
adjustment on May 31 follows:
Dr. Cr.
Cash Tk. 3,500
Supplies 2,200
Prepaid Insurance 2,280
Land 12,000
Lodge 60,000
Furniture 15,000
Accounts Payable Tk. 4,800
Unearned rent 3,300
Mortgage payable 35,000
Capital . 46,380
Rent Revenue 10,300
Advertising Expenses 600
Salaries expenses 3,300
Utilities Expenses 900
Tk.99,780 Tk.99,780
Other data:
(i) Prepaid insurance is a two years policy starting May 1, 2011.
(ii) A count of supplies showed Tk. 800 of unused supplies on May 31.
(iii) Annual depreciation is Tk. 3,000 on the lodge and Tk. 2700 on furniture,
(iv) The mortgage interest rate is 18% and a month's interest has to be recognized.
Tk. 2,000 of mortgage payable will be due in next month.
(v) Two-third ofthe unearned rent has been earned.
(vi) Salaries ofTk. 750 are accrued and unpaid at May 31.
Contd P/6
(35
I~'~
i
;/
.', '.'
=6=
HUM 303Contd ... Q. NO.7
Required:
(a) Prepare a single column income statement for the month.
(b) Prepare an owner's equity statement for the month.
(c) Prepare a classified balance sheet as on May 31.
8. (a) Write short notes (any three)-
(i) Periodicity assumption.
(ii) Matching principle.
(iii) Financial statements.
(iv) Users of accounting information.
(b) Mrs. Rahman started her own consulting firm on May 1, 2011. The following
transactions occurred during the month-
May 1: Mrs. Rahman invested Tk. 70,000 cash in the business.
May 3 Purchased Tk. 600 of supplies on account.
May 5: Paid Tk. 125 to advertise in the country news.
May 9: Receive Tk. 4,000 cash for services provided.
May 12: Withdrew Tk. 1,000 cash for personal use.
May 15: Performed Tk. 6,400 of services on account.
May 20: Paid for the supplies purchased on account on May 3.
May 23: Received a cash payment of Tk. 4,000 for services provided on account on
May 15.
May 26: Borrow Tk. 5,000 from the bank on a note payable.
May 29: Purchase office equipment for Tk. 3,100 on account.
Requirements:
Show the effects of the listed transactions on the accounting equation.