Engineering Science N3 November 2012 Memorandum

Engineering Science N3

Engineering Science N3 Question Papers

November 2012

Question 1

1.1

1.1.1      a = - 3 m/s^2

1.1.2      s = 137,5 m/s

1.1.3      Momentum = 70 000 kg.m/s

1.1.4      Change in KE = 825 kJ

1.1.5      Braking force = 6 000 N

1.2

1.2.1     Torque = 300 Nm

1.2.2      Power = 1,8 kW

Question 2

2.1      Theory

2.2    

2.2.1      Reaction C = 63,75 kN

              Reaction B = 16,25 kN

2.2.2      Shear force diagram

Question 3

3.1      Sum of VC = 41,152 kN;     Sum of HC = 62,64 kN

3.2      CA = 25,456 kN   Strut;       AB = 18 kN    Tie

Question 4

4.1      Theory

4.2

4.2.1      Sketch

4.2.2      Fup = 1039,725 N

Question 5

5.1

5.1.1      Heat released by steel = 1 177,6 kJ

5.1.2      Volume of oil = 17,796 litres

5.2         Final area of aluminium plate = 20 023 mm^2

5.3

5.3.1      hf = 962 kJ

5.3.2      hg = 2 801 kJ

5.3.3      hfg = 1 839 kJ

5.3.4      hws = 2 690,66 kJ

5.3.5      h1 - x = 110,34 kJ

Question 6

6.1

6.1.1      Work done by pump = 6 927,212 kJ

6.1.2      Power required = 192,423 W

6.2

6.2.1      Force exerted by ram , W = 3 826,531 kN

6.2.2      Distance moved by ram, H = 0,063 m

6.2.3      Number of pumping strokes = 734

6.2.4      Volume of liquid received = 2 258,02 litres

Question 7

7.1

7.1.1      Total resistance = 6,463 ohms

7.1.2      Total current flow = 2,872 A

7.2

7.2.1      Current through lamp = 0,625 A

7.2.2      Resistance of lamp = 384 ohms

7.2.3      Costs = 2,7 cents

Question 8

8.1     Theory

8.2     Theory

8.3     Theory