Grade 11 Technical Sciences Paper 1 Exemplary 2017

National Senior Certificate

• Grade 11 Technical Sciences: Paper 1
• Examplar 2017

Instructions and Information

• Answer all eight questions in the answer book
• Start each question on a new page
• Number answers according to the paper's numbering system
• Leave one line between sub-questions
• A non-programmable calculator can be used
• Appropriate mathematical instruments may be used
• Use the attached data sheet
• Show all formulae and substitutions in calculations
• Round final answers to at least two decimal places
• Give brief motivations, discussions, etc., where needed
• Write neatly and legibly

Question 1: Multiple Choice Questions

• Answer all multiple-choice questions (1.1-1.10) in the answer book.
• Choose the correct answer (A-D) and mark an X over the corresponding letter.
• Example:
  • 1.11: A B C D (mark an X over the correct letter)
• The SI unit for force is the Newton (1.1)
• The y-axis on a Cartesian plane represents the vertical component (1.2)
• Vectors are represented by the symbol V (or a bold letter) (1.3)
• The longest side of a right-angled triangle opposite the right angle is called the hypotenuse (1.4)
• Frictional force is dependent on the normal force and opposes motion (1.5)
• A piece of metal is attracted to a magnet (1.6)
• Halving the distance between two charged spheres quadruples the electrostatic force between them (1.7)
• Positive charge at a higher potential at point 2 than at point 3 (1.8)
• The unit of flow of charge is the ampere (1.9)
• At a distance x from the positive plate of a capacitor, the electric field is E. At a distance -x from the positive plate the electric field will be E (1.10)

Question 2:

• 2.1 Define the term resultant.
• 2.2 Label the parts A, B, and C of the diagram.
• 2.3 Calculate the total force if two forces of 100N and 80N are exerted on an object.
• 2.4 Calculate and graphically determine the direction of displacement for a person walking 6 meters east and then 5 meters north.

Question 3:

• 3.1 Graphically determine the magnitude and direction of the resultant force using a scale of 1mm = 5N.
• 3.2.1 Calculate the horizontal component of a 60N force exerted at a 40-degree angle to the horizontal.
• 3.2.2 Calculate the vertical component of the 60N force exerted at a 40-degree angle to the horizontal.
• 3.2.3 Graphically show the horizontal and vertical components.

Question 4:

• 4.1 Define frictional force.
• 4.2 Calculate the maximum static frictional force for a 3kg box on a table pushed with 50N force to the right given µs = 0.35.
• 4.3 Draw a free body diagram for the box indicating all forces
• 4.4 Calculate the kinetic frictional force given that kinetic friction is 40% of the normal force.

Question 5:

• 5.1 Define the term magnetic field.
• 5.2.1 Identify three mistakes in a learner's diagram of a magnetic field.
• 5.2.2 Name the device used to determine the magnetic field direction.
• 5.2.3 Draw a sketch of a broken bar magnet, showing poles.
• 5.3 Describe why the aurora borealis is visible near the North Pole and how it's formed.
• 5.4 Compare Earth's magnetic field with a bar magnet's.
• 5.5 Explain why Earth's magnetic field is important.

Question 6:

• 6.1 Sketch the electric field pattern around a +3 × 10⁻⁹ C charged sphere.
• 6.2 State Coulomb's law in words.
• 6.3 Calculate the electrostatic force between a +3 × 10⁻⁹ C charged sphere and a -2 × 10⁻⁹ C charged sphere separated by 5 cm.
• 6.4.1 Define electric field at a point.
• 6.4.2 Draw the electric field pattern between two oppositely charged particles.
• 6.4.3 Calculate the net electric field strength at point P due to two charges (X and Y).
• 6.4.4 Calculate the magnitude and direction of the electrostatic force on an electron if placed at point P.

Question 7:

• 7.1 Redraw the diagram of parallel plates and indicate the direction of electric field lines.
• 7.2 Explain the implications of parallel and equally spaced electric field lines.
• 7.3 Calculate the electric field between two parallel plates with a 12 V power source and 16 cm separation.

Question 8:

• 8.1 State Ohm's law in words.
• 8.2.1 Calculate the current through the 4Ω resistor.
• 8.2.2 Calculate the total current in the circuit.
• 8.2.3 Calculate resistance X.
• 8.3 Explain why the 4Ω resistor gets warmer than the 6Ω resistor.

Question 9:

• 9.1 Why does the voltmeter reading decrease when switch S is closed? (brief explanation)
• 9.2.1 Calculate the current in the 2Ω resistor.
• 9.2.2 Calculate the reading on the ammeter.

Question 10:

• 10.1 Which value is the dependent variable in the graph?
• 10.2.1 Locate the point on the graph where Ohm's Law is no longer obeyed.
• 10.2.2 Describe a possible reason for the deviation from Ohm's Law.
• 10.3 Calculate the gradient of the obeyed portion of the graph, and use it to calculate the resistance of the conducting wire.