The following shows the flow of conventional current through the coils. Indicate on the diagram the North and South Poles as well as the direction of the current through the coils.
Watch the video on d.c. motors to help you understand how a current carrying conductor can experience a force.
Question 6
6.
Question 7
7.
The following image explains why the force exerted on the current carrying conductor exists and also in which direction it is exerted.
Watch the video to see how the split-ring commutator aids the continuous rotation of the armature.
Question 8
8.
Question 9
9.
Question 10
10.
Describe the motion of the armature if the battery was connected directly without an a split ring commutator.
Question 1
1.
Question 2
2.
What type of field surrounds a straight current carrying conductor?
Question 3
3.
Draw the field around the current carrying conductor and include its direction by means of arrows
Question 4
4.
Explain how we can increase the Force acting on a wire according to the following diagram.
Increase
Decrease
Current in wire passing through magnetic Field
Length of conductor in magnetic field
Magnetic field strength
The best angle between the current in the wire and magnetic field, to experience maximum force is? (you may make more than one selection)
Fleming's left hand rule allows us to determine the direction of the force on the wire. Study the rule in the diagram below.
Flemming’s left hand rule
Hold the thumb, first finger and second finger of the left hand at right-angles to each other. Align the second finger with the direction of the current in the conductor. The first finger points in the direction of the external magnetic field.
The thumb points in the direction of the magnetic force or thrust experienced by the conductor and this is the direction that the conductor will move.
Arrange the following choices in the correct sequence in order to explain how a simple d.c. motor works
the magnetic field interacts with the field of the magnet causing a force to be exerted on the coil
d.c. current passes through the coil
which keeps the coil spinning in one direction
the armature rotates
the split ring reverses the direction of the current in the coil every half turn.
one side will experience a force downward and the other side will experience a force upwards
the current creates a magnetic field around the coil
which reverses the forces on acting on the coil
Predict which direction the armature would spin.
Clockwise
Anti-clockwise
What must charge do in order to produce a magnetic field?
move
be positive
be negative
remain stationary
A cross-section of a current carrying conductor is shown.