Grade 12 IEB definitions Physics Exam Questions
and Correct
1. Freefall correct answer: when the only force acting on an object is gravity
2. conventional current correct answer: Current that flows from the positive side of the battery
to the negative side
3. motor effect correct answer: The motor ettect is where a current carrying wire (or any other
conductors) is put between magnetic poles, the magnetic field around the wire interacts with
magnetic field it has been placed in. This causes the
magnet and the conductor to exert forces on each other causing the wire to move either up or down
4. Commutator correct answer: A device that controls the direction of the flow of current through
an electric motor
5. split ring commutator correct answer: A ring with gaps in it that swaps the electrical contacts
of a device every half-turn.
6. Slip ring commutator correct answer: Used to connect the external circuit to the rotating coil
in an AC electric generator.
7. alternating current correct answer: an electric current that reverses its direction many times
a second at regular intervals, typically used in power supplies.
8. Direct Current (DC) correct answer: Electric current that flows in only one direction
9. kinetic energy correct answer: the energy an object has due to its motion
10. work-energy theorem correct answer: The work done on an object equals the change
in kinetic energy of the object
11. Newton's Second Law correct answer: a net force acting on an object causes the
object to accelerate in the direction of the net force
12. Newton's Third Law correct answer: Every action has an equal and opposite
reaction
13. Newton's First Law correct answer: An object at rest stays at rest and an object in
motion stays in motion with the same speed and in the same direction unless acted upon by an
unbalanced force.
14. principle of conservation of momentum correct answer: Total momentum of a
system remains the same before and after a collision
15. conservation of mechanical energy correct answer: Initial mechanical energy =
final mechanical energy
16. correct answer:
1/
1
and Correct
1. Freefall correct answer: when the only force acting on an object is gravity
2. conventional current correct answer: Current that flows from the positive side of the battery
to the negative side
3. motor effect correct answer: The motor ettect is where a current carrying wire (or any other
conductors) is put between magnetic poles, the magnetic field around the wire interacts with
magnetic field it has been placed in. This causes the
magnet and the conductor to exert forces on each other causing the wire to move either up or down
4. Commutator correct answer: A device that controls the direction of the flow of current through
an electric motor
5. split ring commutator correct answer: A ring with gaps in it that swaps the electrical contacts
of a device every half-turn.
6. Slip ring commutator correct answer: Used to connect the external circuit to the rotating coil
in an AC electric generator.
7. alternating current correct answer: an electric current that reverses its direction many times
a second at regular intervals, typically used in power supplies.
8. Direct Current (DC) correct answer: Electric current that flows in only one direction
9. kinetic energy correct answer: the energy an object has due to its motion
10. work-energy theorem correct answer: The work done on an object equals the change
in kinetic energy of the object
11. Newton's Second Law correct answer: a net force acting on an object causes the
object to accelerate in the direction of the net force
12. Newton's Third Law correct answer: Every action has an equal and opposite
reaction
13. Newton's First Law correct answer: An object at rest stays at rest and an object in
motion stays in motion with the same speed and in the same direction unless acted upon by an
unbalanced force.
14. principle of conservation of momentum correct answer: Total momentum of a
system remains the same before and after a collision
15. conservation of mechanical energy correct answer: Initial mechanical energy =
final mechanical energy
16. correct answer:
1/
1
